priyankur_saha@ml.com wrote:

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.

first of all, we are comparing the rate of increase in 1980 to the rate of increase in the 1970.

since we are comparing the same thing, and since we have a preposition "in" at the beginning of the sentence, there is a high probability that the one specifying "in the 1970's" is the right answer.

moreover, A is incorrect, "as fast as" means the same, thus, it can't be twice!!! as fast.

(A) twice as fast as

twice + as fast as - is awkward and incorrect. as fast as means the same.

(B) twice as fast as it was in

same as in A. twice as fast as - incorrect. nevertheless, the it was in is ok.

(C) twice what it was in

looks good, it says that the rate in the 1980 was twice what it was in 1970.

(D) two times faster than that of

two times faster - wordy, moreover, it changes the meaning as it says the rate of 1970, not the rate of of increase of the minority population. than that - implies as smth else is compared, although the only antecedent for "that" is the rate.

(E) two times greater than

greater is used for comparing 2 different things. thus it is incorrect.