In which set of ordered pairs is y a function of x? A. {(1, 3), (2, 3), (3, 3), (4, 3)} B. {(0, 2), (2, 5), (0, 4), (1, 5)} C. {(–1, 5), (2, 6), (4, 8), (–1, 4)} D. {(1, 3), (–2, 5), (–2, 7), (3, 5)}