Which of the following indicators is NOT used to calculate Human Development Index (HDI) ?

1. A

   Life Expectancy

   (a) Life Expectancy. HDI’s health dimension is life expectancy at birth. It is used, so it cannot be the ‘not used’ answer.

2. B

   Education

   (b) Education. Mean years of schooling and expected years of schooling make the education dimension. Education is inside HDI.

3. C

   Per Capita Income

   (c) Per Capita Income. GNI per capita (PPP) is the standard-of-living limb. Income is used.

4. D

   Social Inequality

   (d) Social Inequality. UNDP’s three HDI limbs are health, education and income. Inequality is handled in IHDI and other satellite indices, not in the basic HDI formula. That exclusion is the official key.

Summary. Official key is (d) Social Inequality. Classic HDI combines life expectancy, schooling and per-capita income. Social inequality is a neighbouring UNDP concern (IHDI, Gini) but is not one of the three HDI indicators. Options (a)–(c) are the actual limbs, so they cannot be the ‘not used’ choice.