Name the economist who in 1990 created the Human Development Index(HDI) which are used in Human Development Reports by UNDP ?

Name the economist who in 1990 created the Human Development Index(HDI) which are used in Human Development Reports by UNDP ?
 a) Raj Krishna
 b) J M Keynes
 c) Mahbub ul Haq
 d) Daniel Kahneman

Mahbub ul Haq