If x and y are perfect squares, then which one of the following is not necessarily a perfect square?  Choose the correct choice from the following answers:	A) x^2	B) xy	C) 4x	D) x+y	E) x^5
If x=y=1^2=1, then each option but D is a perfect square, therefore D is NOT necessarily a perfect square.   Answer: x+y.
<result>D</result>
If x and y are perfect squares, then which one of the following is not necessarily a perfect square?