The answer should be (A) - statement (1) alone is sufficient to answer the question. Consider statement (1) first:
X = 3Y^2 + 7Y
=> X = Y (3Y + 7)
=> X = Y * some number
Therefore X is a multiple of Y. So statement (1) alone is sufficient. Next consider statement 2:
X^2 - X is a multiple of Y
=> kY = X(X-1) where k is any integer >= 1
=> X = kY/(X-1) = [k/(X-1)]Y
Therefore X is a multiple of Y depending on whether k/(X-1) is an integer or not.
For k = 4 and X = 5, this works. For k=5, X=5 it does not work.
Therefore statement (2) alone is insufficient to answer the question.
Hence (A) is the correct answer choice.
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