Question

Help pleaseee??

Which of the following represents a function?

A.) x: -2 , -1 , 0 , -1 , -2
y: 2 , 3 , 4 , 5 , 6
B.) x- 1, 2 , 3 , 4 , 5
y- 5 , 4 , 3 , 2 , 1
C.) x- 1, 2 ,1 , 1 , 2 , 1
y- 0 , 1 , 2 , 3 , 4
D.) x- 1 , 1, 1, 1 , 1
y- 2 , 3 , 4 , 5 , 6