Answer:
W
Step-by-step explanation:
The vertical line test is a simple tool to determine if a graph is a function. Draw a vertical line through the graph. If at any point where you draw this line you hit the relation twice or more you know it to not be a function. What I mean is that if you have multiple Y's for a single X, then it cant be a function.
Side note: Vertical is up and down, like the line in X.
