Question

Which relation is a function?

O {(1, 2); (1, 3); (3, 2); (4, 2)}
O {(1, 2); (2, 3); (3, 4); (2,5)}
O {(1, 2); (2, 3); (3, 4); (1,5)}
O {(1, 2); (2,5); (3, 2); (4,5)}

Answer 1

the last one is a function