This is a simple one.
All you need to do is find the scale factor of the shapes. (How much has it decreased by?)
Wecan find this by doing 15 ÷ 20 (not the other way round because we want to find the scale factor for the bigger rectangle to the smaller)
15 ÷ 20 = 0.75
So to find the area all you need to do is times the area with the scale factor which is 0.75
500 x 0.75 = 375cm²
So the answer is
(A) 375cm²