Firstly, the xy≠0 part here isn't important. It's merely to satisfy any math nerds out there who would protest that if xy = 0, this question is undefined. Nerds!
Secondly, let's solve this. When you have a fraction with terms being added or subtracted in the denominator, a good thought is to split it into two fractions. Thus:
x1xy
can be split into
x 
1xy xy
which simplifies to
1 
1y xy
This leads us to answer choice D.
METHOD TWO: Another way to solve this problem, or almost any other problem with variables in the answer choices, would be to pick a couple of values for x and y, for example 2 and 3, respectively, and plug them into the original equation. This results in a value of 1/6. Then plug 2 and 3 into every answer you see, and you will find that only answer choice D results in a value of 1/6. Thus, only D can be the correct answer.
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