If x > 1, then 1/x is between 0 and 1. So 1 + (1/x) will be between 1 and 2, and answers C and E are both possible (for C, x = 7/2, and for E, x = 7). If there's a typo in D, and instead it's meant to read "15/11", then D is also possible (x = 11/4). It's only if the question tells you x is an integer that E becomes the lone correct answer among the choices, but the question doesn't tell us that.
So the question has two or three right answers, which can't happen on the GMAT - where is it from?
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