Question

what is human development index.​

Answer 1

The Human Development Index is a statistic composite index of life expectancy, education, and per capita income indicators, which are used to rank countries into four tiers of human development. 

Answer 2

$\huge\underbrace\mathcal\pink{AnSwEr}$

$\longrightarrow$ Literacy rate

$\longrightarrow$ Per capita income

$\longrightarrow$ Life expectancy