The answer is D.
Find the scale of each dimension:
B: 6/3 = 2 and 10/5 = 2, both dimensions have the same scale factor of 2.
C: 15/3 = 5 and 25/5 = 5, both dimensions have the same scale factor of 5.
D: 60/3 = 20 and 90/5 = 18, each dimension has a different scale factor so is not an enlargement.
