Question

Plz help I need to graduate 15 pls!

Which of the following relations is a function?
A.
{(2, 2), (3, 3), (4, 4), (5, 5)}
B.
{(2, 1), (2, 3), (3, 6), (3, 7)}
C.
{(3, 5), (4, 9), (4, 11), (5, 14)}
D.
{(4, 8), (6, 6), (8, 4), (8, 2)}

Answer 1

The answer is A because X can’t have the same numbers for it to be a function.