Which of the following represents a relation that is not a function?

A function is for every input, there is 1 output
aka
x never repeats with a different y

A. x doesn't repeat, it's a function

B. -8 repeats with 34 and 40, this is not a funciton (this is the answer0

C. x doesn't repeat, it's a function

D. x doesn't repeat, it's a function

answer is B