The correct answer is B. Human Development Index.
The Human Development Index (HDI) takes into consideration several different factors in order to categorize nations as to levels of development. Some of the factors they use are:
A) A country's Gross National Income (GNI)
B) Life expectancy
C) Education of citizens (i.e. college degree, years of schooling for average citizen).
<span>B.) Many cities in the United States allow all of their citizens to vote on laws.
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