Which relation is a function? A. {(1, 2); (1, 3); (1, 4); (1, 5)} B. {(1, 2); (2, 3); (3, 4); (1, 5)} C. {(1, 2); (2, 2); (3, 2); (4, 2)} D. {(1, 2); (2, 3); (3, 4); (2, 5)}

ANSWER ASAP