At Shiprock, New Mexico, a perennially powerful girls' high school basketball team has become a path to college for some and a source of pride for a community where the household incomes of 49 percent of them are below the poverty level.

(A) where the household incomes of 49 percent of them are
(B) where they have 49 percent of the household incomes
(C) where 49 percent of the household incomes are
(D) which has 49 percent of the household incomes
(E) in which 49 percent of them have household incomes

Can someone please explain the answer.Why is it "C"