Does this set of ordered pairs represent a function? Why or why not?

{ (-2,2), (-1,2), (3,-1), (3, 1), (4,11) }

A. No, because one x-value corresponds to two different y-values.

B. Yes, because there are two x-values that are the same.

C. Yes, because every x-value corresponds to exactly one y-value.

D. No, because two of the y-values are the same.