Answer:
B.
Explanation:
A function is where every input has exactly one output, or one x for every y.
The x term may not be repeated, for example.
(3,5) (2,-2) (8,5)
This is a function because even though there is a repeating y value (5), the x value is not repeated.
(6,2) (-3,4) (6,8)
This is not a function because the x term(6) repeats.
If you look at the relations, you can see that the only option with repeating x values is B. (has two 9 terms).
B. is not a function