Answer: Choice A
No, because one x value corresponds to two different y values.
We have x = 3 map to both y = 4 and y = 3 simultaneously. A function is only possible when any x value leads to exactly one y value only.
If you plotted the points, then you should see that they fail the vertical line test. Specifically the points (3,4) and (3,3) are the reason why.
