Problem Solving (PS) | For all nonzero numbers x and y, operation x#y is equal to y#x. Operat

For all nonzero numbers x and y, operation x#y is equal to y#x. Operation # could be defined by which of the following operations?

I. x#y = y/x + x/y
II. x#y = x/y - y/x
III. x#y = x^2 - 2xy + y^2

(A) I only
(B) II only
(C) III only
(D) I and II
(E) I and III

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