D. 3/4 because 12 of the 16 rectangles are filled in and if you divide the 16 and 12 by 4 they would equal 4 and 2. This shows that 16 and 12 are a product of 4 times another number. So if 12 are filled in only 4 more have to be filled in and 12 divided by 4 equals 3. So in this case the answer is 3/4.