If y = 6x − 3, which of the following sets represents possible inputs and outputs of the function, represented as ordered pairs? (4 points) {(0, 3), (−2, 15), (4, 21)} {(0, −3), (2, 9), (4, 21)} {(0, −3), (2, 15), (4, 21)} {(0, 3), (1, −9), (2, −15)}