Which relation is not a function?

D.

Step-by-step explanation:

For a relation to be a function, one input cannot have multiple outputs.

In D, we can see that the input x = 1 will yield y = 4 and y = 1. So which one is it?

We cannot determine that, so this relation is not a function.

i can't read the graph

step-by-step explanation:

there is no question content here, but you for the free points! : d