Many Economic Measures Focus on the Average Income of Citizens

Many economic measures focus on the average income of citizens in a given country.Why might this measure be problematic?

A) It can hide income inequality within a given country.
B) It tries to quantify human relations, which are unquantifiable.
C) It attempts to make broad statements based on narrow collections of data.
D) It does not take into account religion and its effects on income.
E) It ignores whether certain populations are naturally thriftier than others, thus requiring different metrics for making meaningful comparisons.