if x > 0 and y > 0, which of the following expressions is the equivalent to (x-y)/(\sqrt(x)-\sqrt(y))
A(x-y)/(\sqrt(x-y))
B\sqrt(x-y)
C\sqrt(x)+\sqrt(y)
D\root(x)(x)+\root(y)(y)
A(x-y)/(\sqrt(x-y))
B\sqrt(x-y)
C\sqrt(x)+\sqrt(y)
D\root(x)(x)+\root(y)(y)