chloecher chloecher 28-09-2017 Mathematics contestada Which of the following relations is a function? a. {(-1, 4), (1,3), (2, 3), (3, 1)} b. {(2,3), (4, 8), (1,3), (2, 4)} c. {(2, 3), (3, 1), (2, 1), (3, 2)} d. {(1, 1), (1, 2), (1, 3), (1, 4)} I think its a