Hint for process of elimination: Since $latex y &s=1$ and $latex xy &s=1$ are both positive, $latex x &s=1$ is also positive. Therefore $latex y-x<y=15 &s=1$. This eliminates choice E, leaving you with four choices. Some awareness about how big or small the answer should be, for example noting that $latex x=8 &s=1$, may help you eliminate choice D for being too big, and choice A for being too small.
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