If y − 3 = 3x, which of the following sets represents possible inputs and outputs of the function, represented as ordered pairs?

a. {(0, 3), (1, 6), (2, 9)}
b. {(3, 0), (6, 1), (9, 2)}
c. {(1, 3), (2, 6), (3, 9)}
d. {(3, 1), (6, 2), (9, 3)}