Question

Choose the best definition for a function.

A. The inputs of a relation

B. The outputs of a relation

C. The movement of a graph either vertically or horizontally.

D. A special relation where every input has only one output.

Answer 1

I believe its answer is D.
A function is a relation from a set of possible outputs where each input is related to exactly one output. I how this is what you're looking for.