UPSC CSE 2026 Essay Paper Discussion

YEAR ASKED IN

2024

Practice UPSC 2024 previous year questions on Anantam IAS: 100 Prelims MCQs and 80 Mains Q&A with answer keys, explanations and topic-wise links.

Prelims MCQs 100

  1. Consider the following statements in respect of the digital rupee : 1. It is…

    Consider the following statements in respect of the digital rupee : 1. It is a sovereign currency issued by the Reserve Bank of India (RBI) in alignment with its monetary policy. 2. It appears as a liability on the RBI's balance sheet. 3. It is insured against inflation by its very design. 4. It is freely convertible against commercial bank money and cash. Which of the statements given above are correct?

    1. A1 and 2 only
    2. B1 and 3 only
    3. C2 and 4 only
    4. D1, 2 and 4
    Answer and explanation

    Correct answer: D

    * Statement 1 is correct. The digital rupee, also known as the e-rupee or Central Bank Digital Currency (CBDC), is indeed a sovereign currency issued by the RBI. It's a digital representation of India's fiat currency and is part of the RBI's monetary policy toolkit.

    * Statement 2 is correct. Like physical currency, the digital rupee is a liability on the RBI's balance sheet. When you hold digital rupees, it's essentially a claim you have on the RBI, similar to holding physical banknotes.

    * Statement 3 is incorrect. The digital rupee, by itself, doesn't come with inherent inflation protection. Its value, like physical currency, is subject to inflationary pressures. The RBI manages inflation through its monetary policy measures, not through the inherent design of the digital rupee.

    * Statement 4 is correct. The digital rupee is designed to be freely convertible. This means you can easily exchange it with bank deposits (commercial bank money) and cash at a 1:1 ratio without any restrictions.

    Therefore, the correct answer is (D) 1, 2 and 4.

  2. Recently, the term “pumped-storage hydropower” is actually and appropriately discussed in the context of…

    Recently, the term "pumped-storage hydropower" is actually and appropriately discussed in the context of which one of the following?

    1. AIrrigation of terraced crop fields
    2. BLift irrigation of cereal crops
    3. CLong duration energy storage
    4. DRainwater harvesting system
    Answer and explanation

    Correct answer: C

    Pumped-storage hydropower (PSH) is used for long-duration energy storage. It works by pumping water to a higher reservoir during low electricity demand and releasing it to generate power during peak demand. This process helps balance the grid supply and demand, making PSH an effective tool for energy storage over extended periods.

    Thus, the correct answer is C.

  3. One of the following regions has the world’s largest tropical peatland, which holds about…

    One of the following regions has the world's largest tropical peatland, which holds about three years worth of global carbon emissions from fossil fuels; and the possible destruction of which can exert detrimental effect on the global climate. Which one of the following denotes that region?

    1. AAmazon Basin
    2. BCongo Basin
    3. CKikori Basin
    4. DRio de la Plata Basin
    Answer and explanation

    Correct answer: B

    The Congo Basin is home to the Cuvette Centrale, which is the world's largest tropical peatland complex. Spanning the Republic of Congo and the Democratic Republic of Congo, this peatland covers about 145,000 square kilometres and stores approximately 30 billion tonnes of carbon—a value roughly equivalent to three years of global fossil fuel emissions. The protection of this region is highlighted by the Brazzaville Declaration (2018), signed by the Republic of Congo, the Democratic Republic of Congo, and Indonesia, to prevent land-use changes and drainage that would release this stored carbon and exacerbate global climate change.

  4. With reference to “Coriolis force”, which of the following statements is/are correct? 1. It…

    With reference to "Coriolis force", which of the following statements is/are correct? 1. It increases with increase in wind velocity. 2. It is maximum at the poles and is absent at the equator. Select the answer using the code given below :

    1. A1 only
    2. B2 only
    3. CBoth 1 and 2
    4. DNeither 1 nor 2
    Answer and explanation

    Correct answer: C

    Statement 1 is Correct: The Coriolis force is directly proportional to the velocity of the moving object. Therefore, as wind velocity increases, the magnitude of the Coriolis force acting on it also increases, leading to a greater deflection.

    Statement 2 is Correct: The Coriolis force is proportional to the sine of the latitude. At the equator (0° latitude), the sine of 0° is zero, so the Coriolis force is absent. At the poles (90° latitude), the sine of 90° is 1 (maximum), making the Coriolis force strongest at these points. It is important to note that while the linear velocity of Earth's rotation is highest at the equator and zero at the poles, the Coriolis effect depends on the rotation of the coordinate system itself, which is most pronounced at the poles.

  5. With reference to Union Budget, consider the following statements : 1. The Union Finance…

    With reference to Union Budget, consider the following statements : 1. The Union Finance Minister on behalf of the President lays the Annual Financial Statement before both the Houses of Parliament. 2. At the Union level, no demand for a grant can be made except on the recommendation of the President of India. Which of the statements given above is/are correct?

    1. A1 only
    2. B2 only
    3. CBoth 1 and 2
    4. DNeither 1 nor 2
    Answer and explanation

    Correct answer: C

    Statement 1 is Correct: Under Article 112, the President causes the Annual Financial Statement (Union Budget) to be laid before Parliament. In practice, the Union Finance Minister presents the Budget on behalf of the President before both Houses of Parliament.

    Statement 2 is Correct: Article 113(3) of the Constitution explicitly provides that no demand for a grant shall be made except on the recommendation of the President of India. This ensures executive control over the proposal of expenditures from the Consolidated Fund of India.

  6. Which one of the following is the correct description of “100 Million Farmers”?

    Which one of the following is the correct description of "100 Million Farmers"?

    1. AIt is a platform for accelerating the transition towards food and water systems that are net-zero (carbon), nature-positive and that aims to increase farmer resilience.
    2. BIt is an international alliance and a network of individuals and farming organisations interested in supporting and strengthening the development of the organic animal husbandry.
    3. CIt is a digital platform fully integrated with service providers and built on blockchain that lets buyers, sellers and third parties trade fertilizers quickly and securely.
    4. DIt is a platform with the mission of encouraging the farmers to form Farmer Product Organisations or Agribusiness Consortiums, thus facilitating the access to global open markets to sell their products.
    Answer and explanation

    Correct answer: A

    The 100 Million Farmers is a global initiative launched by the World Economic Forum (WEF). It serves as a platform to accelerate the transition toward food and water systems that are net-zero, nature-positive, and resilient. The program aims to support 100 million farmers by 2030 in adopting regenerative agriculture practices, which improve soil health, sequester carbon, and enhance biodiversity while securing farmer livelihoods.

    Option B is Incorrect: This description refers to general organic animal husbandry networks, whereas the 100 Million Farmers initiative focuses on broader regenerative agriculture and climate-resilient food systems.

    Option C is Incorrect: This describes a blockchain-based fertilizer trading platform, which is not the objective of this initiative.

    Option D is Incorrect: While farmer collectives are important, the primary mission of "100 Million Farmers" is the transition to sustainable, net-zero, and nature-positive agricultural practices rather than just facilitating market access through FPOs.

  7. Consider the following statements regarding World Toilet Organization : 1. It is one of…

    Consider the following statements regarding World Toilet Organization : 1. It is one of the agencies of the United Nations. 2. World Toilet Summit, World Toilet Day and World Toilet College are the initiatives of this organization, to inspire action to tackle the global sanitation crisis. 3. The main focus of its function is to grant funds to the least developed countries and developing countries to achieve the end of open defecation. Which of the statements given above is/are correct?

    1. A2 only
    2. B3 only
    3. C1 and 2
    4. D2 and 3
    Answer and explanation

    Correct answer: A

    * Statement 1 is incorrect. The World Toilet Organization (WTO) is not an agency of the United Nations. It is an international non-profit organization.

    * Statement 2 is correct. The WTO is known for its initiatives like World Toilet Summit, World Toilet Day, and World Toilet College, all aimed at addressing the global sanitation crisis.

    * Statement 3 is incorrect. While the WTO advocates for improved sanitation and hygiene, its primary function is not to grant funds. It focuses on advocacy, education, and capacity building to achieve its goals.

    _Therefore, only statement 2 is correct._

  8. With reference to the ‘Pradhan Mantri Surakshit Matritva Abhiyan’, consider the following statements: 1.…

    With reference to the 'Pradhan Mantri Surakshit Matritva Abhiyan', consider the following statements: 1. This scheme guarantees a minimum package of antenatal care services to women in their second and third trimesters of pregnancy and six months post-delivery health care service in any government health facility. 2. Under this scheme, private sector health care providers of certain specialities can volunteer to provide services at nearby government health facilities. Which of the statements given above is/are correct?

    1. A1 only
    2. B2 only
    3. CBoth 1 and 2
    4. DNeither 1 nor 2
    Answer and explanation

    Correct answer: B

    * Statement 1: Incorrect. The Pradhan Mantri Surakshit Matritva Abhiyan (PMSMA) provides a minimum package of antenatal care (ANC) services only during the second and third trimesters of pregnancy. It does not cover post-delivery health care services for six months. The focus is on ensuring safe pregnancies through early detection and management of high-risk cases.

    * Statement 2: Correct. Under PMSMA, private sector health care providers (such as gynecologists, radiologists, and physicians) can volunteer to provide free services at nearby government health facilities on the 9th of every month. This public-private partnership enhances access to specialized care for pregnant women.

  9. Which of the following statements about the Ethics Committee in the Lok Sabha are…

    Which of the following statements about the Ethics Committee in the Lok Sabha are correct? 1. Initially it was an ad-hoc Committee. 2. Only a Member of the Lok Sabha can make a complaint relating to unethical conduct of a member of the Lok Sabha. 3. This Committee cannot take up any matter which is sub-judice. Select the answer using the code given below :

    1. A1 and 2 only
    2. B2 and 3 only
    3. C1 and 3 only
    4. D1, 2 and 3
    Answer and explanation

    Correct answer: C

    Statement 1 is Correct: The Ethics Committee of the Lok Sabha was first constituted as an ad-hoc committee by the Speaker in 2000. It became a permanent standing committee of the House only in 2015.

    Statement 2 is Incorrect: Any person can make a complaint of unethical conduct against a member of the Lok Sabha. While a complaint made by an outsider must be forwarded by a member of the Lok Sabha, the initiator of the complaint does not necessarily have to be a member of the House.

    Statement 3 is Correct: According to the Rules of Procedure, the Ethics Committee cannot take up any matter that is sub-judice, meaning a matter that is currently under consideration or trial by a court of law.

  10. Consider the following airports: 1. Donyi Polo Airport 2. Kushinagar International Airport 3. Vijayawada…

    Consider the following airports: 1. Donyi Polo Airport 2. Kushinagar International Airport 3. Vijayawada International Airport In the recent past, which of the above have been constructed as Greenfield projects?

    1. A1 and 2 only
    2. B2 and 3 only
    3. C1 and 3 only
    4. D1, 2 and 3
    Answer and explanation

    Correct answer: A

    * Donyi Polo Airport (Itanagar, Arunachal Pradesh): This newly constructed airport was inaugurated in 2022. It was built on undeveloped land, making it a greenfield project.

    * Kushinagar International Airport (Uttar Pradesh): This airport was inaugurated in 2021. It was also built as a new entity on undeveloped land, qualifying as a greenfield project.

    * Vijayawada International Airport (Andhra Pradesh): This airport has existed for several decades. While it has undergone significant expansion and modernization, it wasn't built from scratch on undeveloped land. Therefore, it's not a greenfield project.

    Therefore, only Donyi Polo Airport and Kushinagar International Airport are greenfield projects.

  11. With reference to the sectors of the Indian economy, consider the following pairs: |…

    With reference to the sectors of the Indian economy, consider the following pairs: | Economic activity | Sector | |---------------------|--------| | 1. Storage of agricultural produce | Secondary | | 2. Dairy farm | Primary | | 3. Mineral exploration | Tertiary | | 4. Weaving cloth | Secondary | How many of the pairs given above are correctly matched?

    1. AOnly one
    2. BOnly two
    3. COnly three
    4. DAll four
    Answer and explanation

    Correct answer: B

    * Storage of agricultural produce | Secondary (Incorrect) - Storage is a tertiary activity. It falls under the service sector, facilitating the smooth flow of goods from producers to consumers.

    * Dairy farm | Primary (Correct) - Dairy farming involves the direct extraction of raw materials (milk) from natural resources (animals). Hence, it's a primary activity.

    * Mineral exploration | Tertiary (Incorrect) - Mineral exploration is a primary activity. It involves extracting raw materials from the earth.

    * Weaving cloth | Secondary (Correct) - Weaving cloth transforms raw materials (cotton, silk, etc.) into a finished product (cloth). This transformation signifies a secondary activity.

    Therefore, only two pairs are correctly matched.

  12. What are the duties of the Chief of Defence Staff (CDS) as Head of…

    What are the duties of the Chief of Defence Staff (CDS) as Head of the Department of Military Affairs? 1. Permanent Chairman of Chiefs of Staff Committee 2. Exercise military command over the three Service Chiefs 3. Principal Military Advisor to Defence Minister on all tri-service matters Select the correct answer using the code given below:

    1. A1, 2 and 3
    2. B1 and 2 only
    3. C2 and 3 only
    4. D1 and 3 only
    Answer and explanation

    Correct answer: D

    1. Permanent Chairman of Chiefs of Staff Committee: This is correct. The CDS is designated as the Permanent Chairman of the Chiefs of Staff Committee (COSC), which includes the chiefs of the Army, Navy, and Air Force.

    2. Exercise military command over the three Service Chiefs: This is incorrect. The CDS does not have direct operational command authority over the three service chiefs. The service chiefs continue to exercise operational command over their respective services. The CDS acts as a coordinator and advisor, promoting jointness and integration among the services.

    3. Principal Military Advisor to Defence Minister on all tri-service matters: This is correct. The CDS acts as the single-point military advisor to the Defence Minister on matters related to all three services. This ensures streamlined and integrated military advice to the political leadership.

    4. Additional Information - The creation of the post of the Chief of Defence Staff was recommended by these committees: Group of Ministers (2001), Naresh Chandra Committee and D.B. Shekatkar Committee.

    Therefore, the correct statements are 1 and 3.

  13. Sanghabhuti, an Indian Buddhist monk, who travelled to China at the end of the…

    Sanghabhuti, an Indian Buddhist monk, who travelled to China at the end of the fourth century AD, was the author of a commentary on :

    1. APrajnaparamita Sutra
    2. BVisuddhimagga
    3. CSarvastivada Vinaya
    4. DLalitavistara
    Answer and explanation

    Correct answer: C

    Sanghabhuti was a prominent Buddhist scholar known for his work on the Sarvastivada school of Buddhism, particularly their Vinaya texts. Vinaya texts focus on monastic rules and discipline. He traveled to China to translate these texts, making them accessible to Chinese Buddhists.

    Let's look at the other options:

    * Prajnaparamita Sutra: These sutras are central to Mahayana Buddhism and focus on the concept of 'emptiness' (sunyata). While important, they are not primarily associated with Sanghabhuti's work.

    * Visuddhimagga: This text, meaning 'Path of Purification,' is a comprehensive Theravada Buddhist treatise written by Buddhaghosa, not Sanghabhuti.

    * Lalitavistara: This Mahayana sutra narrates the life of the Buddha and is not directly linked to Sanghabhuti's scholarship.

  14. Consider the following statements: Statement-I : Sumed pipeline is a strategic route for Persian…

    Consider the following statements: Statement-I : Sumed pipeline is a strategic route for Persian Gulf oil and natural gas shipments to Europe. Statement-II : Sumed pipeline connects the Red Sea with the Mediterranean Sea. Which one of the following is correct in respect of the above statements?

    1. ABoth Statement-I and Statement-II are correct and Statement-II explains Statement-I
    2. BBoth Statement-I and Statement-II are correct, but Statement-II does not explain Statement-I
    3. CStatement-I is correct, but Statement-II is incorrect
    4. DStatement-I is incorrect, but Statement-II is correct
    Answer and explanation

    Correct answer: A

    The Assertion (Statement-I) is Correct: The Sumed (Suez-Mediterranean) pipeline is a critical strategic route for transporting energy resources from the Persian Gulf to Europe. It serves as a vital alternative to the Suez Canal, particularly for Ultra Large Crude Carriers (ULCCs) that are too large to navigate the canal fully loaded.

    The Reason (Statement-II) is Correct: The pipeline physically connects the Red Sea to the Mediterranean Sea. It runs from the Ain Sokhna terminal on the Gulf of Suez to the Sidi Kerir terminal near Alexandria. Crude oil from the Persian Gulf is unloaded from tankers at the Red Sea terminal, transported through the pipeline, and then reloaded onto tankers at the Mediterranean terminal for shipment to European ports.

    Statement-II correctly explains Statement-I because the geographical connection between the Red Sea and the Mediterranean is the specific factor that enables the pipeline to function as a strategic transit bypass for shipments heading to Europe.

  15. Consider the following countries : 1. Finland 2. Germany 3. Norway 4. Russia How…

    Consider the following countries : 1. Finland 2. Germany 3. Norway 4. Russia How many of the above countries have a border with the North Sea?

    1. AOnly one
    2. BOnly two
    3. COnly three
    4. DAll four
    Answer and explanation

    Correct answer: B

    * Finland: Finland borders the Baltic Sea, not the North Sea.

    * Germany: Germany shares a border with the North Sea.

    * Norway: Norway has a long coastline along the North Sea.

    * Russia: Russia does not border the North Sea.

    * In total 7 countries border the North Sea - United Kingdom, Norway, Denmark, Germany, The Netherlands, Belgium, France.

    ![North Sea](https://d39jluplm5thpx.cloudfront.net//north_sea_1156b4c198.jpg)

    Therefore, only Germany and Norway border the North Sea.

  16. The total fertility rate in an economy is defined as:

    The total fertility rate in an economy is defined as:

    1. Athe number of children born per 1000 people in the population in a year.
    2. Bthe number of children born to a couple in their lifetime in a given population.
    3. Cthe birth rate minus death rate.
    4. Dthe average number of live births a woman would have by the end of her child-bearing age.
    Answer and explanation

    Correct answer: D

    * The number of children born per 1000 people in the population in a year. This describes the crude birth rate, not the total fertility rate.

    * The number of children born to a couple in their lifetime in a given population. This is close but not quite accurate. The total fertility rate is calculated for women, not couples.

    * The birth rate minus death rate. This defines the rate of natural increase, which indicates population growth, not fertility.

    * The average number of live births a woman would have by the end of her child-bearing age. This is the correct definition of Total Fertility Rate (TFR). It's a hypothetical measure assuming a woman lives through her childbearing years and experiences the age-specific fertility rates of a given period.

    * In simple terms, TFR tells us the average number of children a woman would have if current birth trends continued.

  17. Consider the following information: | Archaeological Site | State | Description | |—|—|—| |…

    Consider the following information: | Archaeological Site | State | Description | |---|---|---| | 1. Chandraketugarh | Odisha | Trading Port town | | 2. Inamgaon | Maharashtra | Chalcolithic site | | 3. Mangadu | Kerala | Megalithic site | | 4. Salihundam | Andhra Pradesh | Rock-cut cave shrines | In which of the above rows is the given information correctly matched ?

    1. A1 and 2
    2. B2 and 3
    3. C3 and 4
    4. D1 and 4
    Answer and explanation

    Correct answer: B

    * Statement 1 is incorrect. Chandraketugarh, located in West Bengal, not Odisha, was an ancient port city known for its extensive trade networks.

    * Statement 2 is correct. Inamgaon is a well-known archaeological site in Maharashtra, providing valuable insights into the Chalcolithic period.

    * Statement 3 is correct. Kerala has numerous megalithic sites, The megalithic monuments at Mangadu consisted of 28 hard compact and unhewn laterite blocks within an area of 5 cents of land.

    * Statement 4 is incorrect. Salihundam, is a village and panchayat in Gara Mandal of Srikakulam district in Andhra Pradesh. It is a historically important Buddhist monument of ancient Kalinga, not rock-cut caves.

    Therefore, the correctly matched rows are 2 and 3.

  18. Consider the following activities: 1. Identification of narcotics on passengers at airports or in…

    Consider the following activities: 1. Identification of narcotics on passengers at airports or in aircraft 2. Monitoring of precipitation 3. Tracking the migration of animals In how many of the above activities can the radars be used?

    1. AOnly one
    2. BOnly two
    3. CAll three
    4. DNone
    Answer and explanation

    Correct answer: B

    * Statement 1 is incorrect: This is typically done using X-ray scanners or advanced imaging technologies like millimeter wave scanners, not traditional radar.

    * Statement 2 is correct: Radars, specifically weather radars, are commonly used to monitor precipitation. They can detect rain, snow, and other weather conditions by bouncing radio waves off precipitation particles.

    * Statement 3 is correct: Radars can be used to track the migration of birds and other animals. They are often used in ornithological studies to monitor bird migration patterns.

  19. With reference to perfluoroalkyl and polyfluoroalkyl substances (PFAS) that are used in making many…

    With reference to perfluoroalkyl and polyfluoroalkyl substances (PFAS) that are used in making many consumer products, consider the following statements : 1. PFAS are found to be widespread in drinking water, food and food packaging materials. 2. PFAS are not easily degraded in the environment. 3. Persistent exposure to PFAS can lead to bioaccumulation in animal bodies. Which of the statements given above are correct?

    1. A1 and 2 only
    2. B2 and 3 only
    3. C1 and 3 only
    4. D1, 2 and 3
    Answer and explanation

    Correct answer: D

    * Statement 1 is Correct. PFAS are used in a wide range of consumer products, and due to their persistence, they can leach into the environment and contaminate water sources, food, and packaging materials.

    * Statement 2 is Correct. PFAS are known as 'forever chemicals' because the strong carbon-fluorine bond makes them highly resistant to natural degradation processes. This persistence leads to their accumulation in the environment.

    * Statement 3 is Correct. Because PFAS don't break down easily, they can build up in the tissues of animals and humans over time, leading to potential health concerns.

    ![PFAS](https://d39jluplm5thpx.cloudfront.net//pfas_products_3012eaeeda.jpeg)

    _Therefore, all three statements are correct._

  20. The longest border between any two countries in the world is between :

    The longest border between any two countries in the world is between :

    1. ACanada and the United States of America
    2. BChile and Argentina
    3. CChina and India
    4. DKazakhstan and Russian Federation
    Answer and explanation

    Correct answer: A

    The border between Canada and the United States is the longest international border in the world, stretching approximately 8,891 kilometers (5,525 miles), including the border shared with Alaska. It is a peaceful boundary and includes both land and water segments.

    ![Border](https://d39jluplm5thpx.cloudfront.net//north_america_01a3d55d0d.jpg)

    Chile and Argentina:

    * Length: Approx. 5,308 kilometres

    * This is the third-longest international border in the world and the longest in South America.

    * It follows the Andes mountain range for most of its length, with several high-altitude border crossings.

    China and India:

    * Length: Approx. 3,488 kilometers * It is highly disputed in areas such as Aksai Chin and Arunachal Pradesh, leading to occasional tensions between the two nations.

    Kazakhstan and Russian Federation:

    * Length: Approx. 7,644 kilometers

    * This is the second-longest international border in the world.

    * It is largely flat, passing through vast steppes, and is a vital region for trade and natural resources between the two countries.

  21. Consider the following: 1. Carabid beetles 2. Centipedes 3. Flies 4. Termites 5. Wasps…

    Consider the following: 1. Carabid beetles 2. Centipedes 3. Flies 4. Termites 5. Wasps Parasitoid species are found in how many of the above kind of organisms?

    1. AOnly two
    2. BOnly three
    3. COnly four
    4. DAll five
    Answer and explanation

    Correct answer: B

    1. Carabid beetles: Many carabid beetles are predatory, and some species are known to be parasitoids, particularly of other insects.

    2. Centipedes: Centipedes are predatory arthropods and not parasitoids. They hunt and kill their prey.

    3. Flies: The order Diptera (flies) includes a large number of parasitoid species. For example, Tachinid flies are parasitoids of various insects.

    4. Termites: Termites are not parasitoids. They are social insects that primarily feed on wood and other plant matter.

    5. Wasps: The order Hymenoptera (wasps, bees, ants) has numerous parasitoid species. Many wasp species are parasitoids, laying their eggs on or in other insects.

    _Therefore, parasitoid species are found in Carabid beetles, Flies, and Wasps._

  22. According to the Environmental Protection Agency (EPA), which one of the following is the…

    According to the Environmental Protection Agency (EPA), which one of the following is the largest source of sulphur dioxide emissions?

    1. ALocomotives using fossil fuels
    2. BShips using fossil fuels
    3. CExtraction of metals from ores
    4. DPower plants using fossil fuels
    Answer and explanation

    Correct answer: D

    Power plants burning fossil fuels (coal, oil, and, to a lesser extent, natural gas) are the largest source of sulfur dioxide emissions globally. Coal, in particular, contains high levels of sulfur, and when burned, it releases large amounts of SO₂.

    * Locomotives, especially older ones, use diesel fuel which contains sulfur. While locomotives do contribute to sulfur dioxide (SO₂) emissions, their contribution is relatively minor compared to larger industrial sources.

    * Ships, particularly large cargo vessels and tankers, often use bunker fuel, a heavy, sulfur-rich fuel oil. This contributes significantly to SO₂ emissions, particularly in maritime regions. However, they are still overshadowed by emissions from power plants

    * The process of extraction of metals from ore involves heating ores that contain sulfur compounds, releasing SO₂ into the atmosphere. However, its contribution is less than that of power plants.

  23. Consider the following: 1. Battery storage 2. Biomass generators 3. Fuel cells 4. Rooftop…

    Consider the following: 1. Battery storage 2. Biomass generators 3. Fuel cells 4. Rooftop solar photovoltaic units How many of the above are considered "Distributed Energy Resources"?

    1. AOnly one
    2. BOnly two
    3. COnly three
    4. DAll four
    Answer and explanation

    Correct answer: D

    Distributed Energy Resources (DERs) are small-scale units of power generation or storage that are situated closer to the end-users. Let's analyze each option:

    * Battery storage: These store energy and can be deployed within the distribution network or at the consumer end, making them DERs.

    * Biomass generators: These can be small-scale and located near the biomass source, making them suitable for distributed generation.

    * Fuel cells: Similar to biomass generators, fuel cells can be deployed in a decentralized manner, qualifying as DERs.

    * Rooftop solar photovoltaic units: These are a classic example of DERs, generating power at the point of consumption.

    _Therefore, all four options are considered Distributed Energy Resources._

  24. Which of the following statements about ‘Exercise Mitra Shakti-2023’ are correct? 1. This was…

    Which of the following statements about 'Exercise Mitra Shakti-2023' are correct? 1. This was a joint military exercise between India and Bangladesh. 2. It commenced in Aundh (Pune). 3. Joint response during counter-terrorism operations was a goal of this operation. 4. Indian Air Force was a part of this exercise. Select the answer using the code given below :

    1. A1, 2 and 3
    2. B1, 2 and 4
    3. C1, 3 and 4
    4. D2, 3 and 4
    Answer and explanation

    Correct answer: D

    * Statement 1 is incorrect: Exercise MITRA SHAKTI-2023 was a joint military exercise between India and Sri Lanka.

    * Statement 2 is correct: The ninth edition of Joint Military exercise "Exercise MITRA SHAKTI-2023" commenced in Aundh (Pune).

    * Statement 3 is correct: The Scope of the exercise includes synergizing joint responses during counter-terrorist operations.

    * Statement 4 is correct: 15 personnel from Indian Air Force and five personnel from Sri Lankan Air Force participated in the exercise.

  25. With reference to radioisotope thermoelectric generators (RTGs), consider the following statements: 1. RTGs are…

    With reference to radioisotope thermoelectric generators (RTGs), consider the following statements: 1. RTGs are miniature fission reactors. 2. RTGs are used for powering the onboard systems of spacecrafts. 3. RTGs can use Plutonium-238, which is a by-product of weapons development. Which of the statements given above are correct?

    1. A1 and 2 only
    2. B2 and 3 only
    3. C1 and 3 only
    4. D1, 2 and 3
    Answer and explanation

    Correct answer: B

    * Statement 1: Incorrect. RTGs (Radioisotope Thermoelectric Generators) are not miniature fission reactors. Fission reactors use nuclear fission, a process of splitting atoms to release a tremendous amount of energy. RTGs, on the other hand, utilize the natural radioactive decay of isotopes to generate heat, which is then converted to electricity through a process called thermoelectricity.

    * Statement 2: Correct. RTGs are indeed a reliable power source for spacecraft, especially those venturing far from the sun where solar panels become ineffective. They provide consistent, low-level electric power for extended periods, making them ideal for probes, satellites, and rovers in deep space.

    * Statement 3: Correct. Plutonium-238 is a common isotope used in RTGs due to its long half-life (the time it takes for half of the material to decay) and its ability to generate a steady heat output from its decay process. While it can be a byproduct of weapons development, there are also alternative ways to produce Plutonium-238 specifically for peaceful applications like RTGs.

  26. Which of the following countries are well known as the two largest cocoa producers…

    Which of the following countries are well known as the two largest cocoa producers in the world?

    1. AAlgeria and Morocco
    2. BBotswana and Namibia
    3. CCôte d'Ivoire and Ghana
    4. DMadagascar and Mozambique
    Answer and explanation

    Correct answer: C

    The Ivory Coast and Ghana are by far the two largest producers of cocoa, accounting for more than 50 per cent of the world's cocoa.

    ![Cocoa](https://d39jluplm5thpx.cloudfront.net//Cocoa_production_8f2f649b22.png)

    West Africa is home to the largest cocoa producing countries worldwide, with 3.9 million tonnes of production in 2022.

    In fact, there are about one million farmers in Côte d'Ivoire supplying cocoa to key customers such as Nestlé, Mars, and Hershey.

    However, the massive influence of this industry has led to significant forest loss to plant cocoa trees.

  27. Consider the following pairs: Country – Animal found in its natural habitat 1. Brazil…

    Consider the following pairs: Country - Animal found in its natural habitat 1. Brazil - Indri 2. Indonesia - Elk 3. Madagascar - Bonobo How many of the pairs given above are correctly matched ?

    1. AOnly one
    2. BOnly two
    3. CAll three
    4. DNone
    Answer and explanation

    Correct answer: D

    1. Brazil - Indri: Indris are _lemurs_ found only in Madagascar, not Brazil. So, this pair is incorrect.

    2. Indonesia - Elk: Elks are found in North America, Europe, and Asia, but not in Indonesia. This pair is incorrect.

    ![Indri - Bonobo- Elk](https://d39jluplm5thpx.cloudfront.net//Indri_c5910efc84.png)

    3. Madagascar - Bonobo: Bonobos are found in the Democratic Republic of Congo, not Madagascar. This pair is also incorrect.

    Therefore, none of the pairs are correctly matched.

  28. Which of the following is/are correctly matched in terms of equivalent rank in the…

    Which of the following is/are correctly matched in terms of equivalent rank in the three services of Indian Defence forces? |Army | Airforce | Navy| |------- | -------- | --------| |1. Brigadier | Air Commodore| Commander| |2. Major General | Air Vice Marshal | Vice Admiral| |3. Major | Squadron Leader | Lieutenant Commander| |4. Lieutenant Colonel | Group Captain | Captain| Select the correct answer using the code given below:

    1. A1 and 4
    2. B1 and 3
    3. C2, 3 and 4
    4. D3 only
    Answer and explanation

    Correct answer: D

    Pair 1 is incorrect: A Brigadier (Army) is equivalent to an Air Commodore (Air Force) and a Commodore (Navy). A Commander in the Navy is actually two ranks junior to a Brigadier.

    Pair 2 is incorrect: A Major General (Army) is equivalent to an Air Vice Marshal (Air Force) and a Rear Admiral (Navy). A Vice Admiral is a rank higher (equivalent to a Lieutenant General).

    Pair 3 is correct: A Major (Army) is equivalent to a Squadron Leader (Air Force) and a Lieutenant Commander (Navy).

    Pair 4 is incorrect: A Lieutenant Colonel (Army) is equivalent to a Wing Commander (Air Force) and a Commander (Navy). A Group Captain and Captain (Navy) are equivalent to a Colonel in the Army.

    The correct equivalent rank in the three services of Indian Defence forces are:

    ![Defense Rank](https://d39jluplm5thpx.cloudfront.net//rank_defence_51adab148f.png)

    | Indian Army | Indian Navy | Indian Air Force | | --------------- | ---------------------- | -------------------------- | | Field Marshal | Admiral of the fleet | Marshal of the Air Force | | General | Admiral | Air Chief Marshal | | Lt. General | Vice Admiral | Air Marshal | | Major General | Rear Admiral | Air Vice Marshal | | Brigadier | Commodore | Air Commodore | | Colonel | Captain | Group Captain | | Lt. Colonel | Commander | Wing Commander | | Major | Lt. Commander | Squadron Leader | | Captain | Lieutenant | Flight Lieutenant | | Lieutenant | Sub Lieutenant | Flying Officer |

    Thus only pair 3 is correctly matched, hence option D is the correct answer

  29. With reference to “water vapour”, which of the following statements is/are correct? 1. It…

    With reference to "water vapour", which of the following statements is/are correct? 1. It is a gas, the amount of which decreases with altitude. 2. Its percentage is maximum at the poles. Select the answer using the code given below :

    1. A1 only
    2. B2 only
    3. CBoth 1 and 2
    4. DNeither 1 nor 2
    Answer and explanation

    Correct answer: A

    * Statement 1: Correct - Water vapour is indeed a gas, and its concentration generally decreases with altitude. This is because the air gets colder as we go higher, and colder air has a lower capacity to hold moisture.

    * Statement 2: Incorrect - The percentage of water vapour in the atmosphere is highest near the equator and decreases as we move towards the poles. This is because the tropics receive the maximum solar radiation, leading to higher temperatures and more evaporation, which in turn increases the amount of water vapour in the air.

  30. Consider the following plants: 1. Groundnut 2. Horse-gram 3. Soybean How many of the…

    Consider the following plants: 1. Groundnut 2. Horse-gram 3. Soybean How many of the above belong to the pea family?

    1. AOnly one
    2. BOnly two
    3. CAll three
    4. DNone
    Answer and explanation

    Correct answer: C

    All three plants—Groundnut, Horse-gram, and Soybean—belong to the pea family, scientifically known as Leguminosae or Fabaceae. This family is characterized by plants that produce legumes (pods containing seeds). Here's a breakdown of each:

    Groundnut (Arachis hypogaea):

    * Groundnut, also known as peanut, belongs to the Leguminosae family. It produces peanuts, which grow underground in pods, typical of legumes.

    * It is part of the subfamily Faboideae, a major division within the pea family.

    Horse-gram (Macrotyloma uniflorum):

    * Horse-gram is another plant in the Leguminosae family. It is commonly cultivated in tropical regions and is known for its high protein content and use in animal feed and food.

    * It belongs to the subfamily Faboideae as well.

    Soybean (Glycine max):

    * Soybean, one of the most important leguminous crops, also belongs to the Leguminosae family. It is widely grown for its edible beans and oil extraction.

    * Soybean is part of the subfamily Faboideae too.

    All three plants are legumes, characterized by their pod-like fruit and ability to fix nitrogen from the atmosphere through a symbiotic relationship with bacteria in their root nodules.

Mains Q&A 80