Bunuel wrote:

If the product of two integers is odd, which of the following must be true?

A. The sum of the two integers is an odd number.

B. The difference between the two integers is an odd number.

C. The square of either integer is an odd number.

D. The sum of the squares of the two integers is an odd number.

E. The difference between the squares of the two integers is an odd number.

If the product of two integers is odd, both integers must be odd, since only odd x odd = odd. Thus, of the answer choices given, only C is true, since the square of an odd integer is also odd.

Answer: C

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Jeffery Miller

Head of GMAT Instruction

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