If x and y are integers and x^2*y is a negative odd integer, which of the following must be true?
I. xy^2 is odd.
II. xy is negative.
III. x + y is even. Choose the correct choice from the following answers
A) I only B) III only C) I and II only D) I and III only E) I, II, and III
x^2*y = negative odd integer   inference:   1. Odd * Odd = Odd   2. y is negative odd integer   3. x is odd (since its squared, the result is positive - so x could be either positive or negative).   Statement I - xy is odd, so is its sqaure - statement must be true   Statement II - xy may or may not be negative - statement may be true but NOT must   Statement III - x and y are odd, so Odd + Odd = Even - statement must be true   Answer is I and III only
<result>D</result>
If x and y are integers and x^2*y is a negative odd integer, which of the following must be true?
I. xy^2 is odd.
II. xy is negative.
III. x + y is even.