Can someone explain to me this ACT question?

Question

fanduekisses · Answer

Which of the following statements about the subsets of real numbers is true?
A. Every integer is a whole number.
B. All rational numbers are integers.
C. 0 is not a real number.
D. 3.14 is a rational number.
E. All integers are negative.

fanduekisses · Answer

The correct answer is D, but wouldn't A be true as well?

fanduekisses · Answer

Can't integers be whole numbers only?

anonymous · Answer

Whole numbers are not negative..integers are

loser66 · Answer

http://www.mathsisfun.com/definitions/whole-number.html

loser66 · Answer

so that negative integer can't be considered as a whole number--> A is not correct

fanduekisses · Answer

Oh so A is incorrect because Every integer cannot be a whole number, because integer can be a negative but whole numbers cannot?

loser66 · Answer

You got it

fanduekisses · Answer

Thanks guys