Which Set of Ordered Pairs Represents a Function from P

Which set of ordered pairs represents a function from P to Q?P = {2, 4, 6, 8} Q = {-5, -3, -1}

A) {(2, -5) , (4, -3) , (4, -1) , (6, -3) , (8, -5) }
B) {(6, -5) , (6, -3) , (6, -1) }
C) {(6, -3) , (4, -5) , (2, -3) , (4, -1) , (6, -5) }
D) {(4, -3) , (6, -1) , (8, -3) }
E) {(2, -1) , (6, -3) , (2, -5) , (6, -1) }