The graph represents the transformation called a horizontal stretch vertical stretch rotation

From the given diagram of the rectangle it is seen that in the original image ABCD, side BC has been re-adjusted to form point B'C', hence we have a new rectangle AB'C'D which is smaller than ABCD. We see that to form ABCD we need to stretch AB'C'D vertically, hence our answer will be:
The graph represents the transformation called vertical stretch

It’s either a or c as the answer.