In each of the four relations below, the x values represent inputs and the y values represent the corresponding outputs. Which relation does not represent a function? * A) { (-2, -3), (1, 3), (3, -3), (5, 3) } B) { (-1, -5), (2, 4), (3, 7), (4, 10) } C) { (-2, 3), (1, 3), (3, 3), (5, 3) } D) { (3, 4), (4, 5), (3, -4), (4, -5) }