Which one of the following is not a sub-index of the World Bank’s “Ease of Doing Business Index”?

The World Bank's Ease of Doing Business Index measured business regulations through 10 specific sub-indices: (1) Starting a business, (2) Dealing with construction permits, (3) Getting electricity, (4) Registering property, (5) Getting credit, (6) Protecting minority investors, (7) Paying taxes, (8) Trading across borders, (9) Enforcing contracts, and (10) Resolving insolvency. While maintenance of law and order is a fundamental requirement for economic stability, it was not one of the quantitative indicators used by the World Bank for this index. Options B, C, and D are all official sub-indices used in the ranking methodology.