Step-by-step explanation
So we have to decide which property we should use first to simplify the expression:

As you can see the properties in options A and D involve two powers with the same base. In this case we don't have more than one power per different base so we can conclude that these two options must be discarded.
Options B and C involve different bases and an exponent outside a parenthesis with an expression inside it. In our case the expression inside parenthesis is a product between x and y² so we can discard C since it has a quotient.
Answer
The only option that wasn't discarded was B so the answer is option B.