In the 1980's the rate of increase of the minority population of the United States
was nearly twice as fast as the 1970's.
(A) twice as fast as
(B) twice as fast as it was in
(C) twice what it was in
(D) two times faster than that of
(E) two times greater than


OA is [spoiler]E

but i went for [/spoiler]b can someone clarify

Thanks in advance