Which sets of ordered pairs represent functions from A to B?A = {3, 4, 5, 6} and B = {-2, -1, 0, 1, 2}a) {(3, 1), (4, -2), (5, 0), (6,2)}b) {(3, 2), (6, 0), (4, 1)}c) {(3, 0), (4, 0), (5, 0), (6, 0)}