Answer:
Not a function.
Does not pass vertical line test.
B.
Explanation:
Something called a vertical line test is used to determine if a relation that has been graphed is a function or not.
We say if it passes then it is a function.
It will pass if you are able to draw infinitely many vertical lines covering the whole graph and each vertical line either touches your relation once or none.
If a single vertical line that you draw touches more than once, then it isn't a function.
When I say draw, I don't mean you should physically do it, but more so imagine it.
Now this particular relation is not a function because I can find a vertical line that touches more than once. Take the vertical line x=5 for example.
It will touch at (5,-6) and (5,6). You cannot have an x assigned to more than one y.