Hello from MrBillDoesMath!
Answer: D ( 44%)
Discussion:
Suppose "x" is the length of a side and "y" is the width. Then
Area = x * y
If "x" is increased by 20%, x becomes 1.2x. Same thing for "y" The area now becomes
Area = 1.2x * 1.2y = 1.44 xy
which is a 44% increase over the area of the original rectangle.
Answer is d.
Thank you,
MrB