Answer: It is a function
Reason: Each x input leads to exactly one and only one y output.
If we had something like (-2,-5) and (-2,3), then those points fail the vertical line test, and we wouldn't have a function.
However, each x input is listed once. We do not have repeated x values. Therefore, the graph passes the vertical line test and we have a function.
The y values are allowed to repeat (but the function wouldn't be one-to-one if the y values repeated).