Answer
D: Opposite.
Work Step by Step
An opposite number is the negative or positive version of the number. To prove this, you add the negative or positive version of the number to the original number to get 0. For example, the opposite of -2 is 2, because -2+2=0 and vice versa, and the opposite of 2 is -2, because 2+-2=0. Therefore, the answer is opposite.