Which relation is also a function?
O [(-1,3), (0, 2), (3, -1), (3, 2)}
O {(2,-4), (2,-2), (2, 1), (2,3)}
O {(0, 3), (1, 2), (1, 4), (2, 1)]}
O{(-4,-3), (0, -3), (1, -3), (4, -3)}