Determine which relation is a function.

A.


Coordinate grid with unlabeled points at negative (two, zero), (negative one, three), (zero, two), (one, negative one), (two, zero), (three, two)

B.


Coordinate grid with unlabeled points at (negative (one, negative one), (negative (one, three), (negative four, three), (negative (two, one), (one, one), (two, negative one)

C.


Coordinate grid with unlabeled points at (negative (two, negative two), (negative two, one), (negative one, three), (zero, one), (two, zero), (two, negative two)

D.


Coordinate grid with unlabeled points at (negative two, one), (negative one, three), (zero, two), (zero, negative one), (one, three), (two, one)