Well im going to say the answer is C, and here's why:
Because 2 out of 3 as a percent is 66.6%, and 8 out of 12 as a percent is 66.6% also.
I say A is wrong because the proportions are out of whack because one goes over a hundred. B is wrong because, 1 out of 6 as a percent is 16.6% and 3 out of 8 as a percent is 37.5 . And D is wrong because 3 out of 4 as a percent is 75% and 9 out of 16 as a percent is 56%. So none of them give you an equal amount besides C.