We are given the graph of the function.
We need explain if given graph represents a function or not.
We can see that graph has three zeros at x=-3,1 and 3.
So, the graph is the graph of a cubic function.
In order to explain if graph represents a function or not, we can apply a vertical line test.
If a vertical line cross the graph at two different points, it would fail the vertical line test.
If we draw different vertical lines at different points on the graph, we get exactly one point and line would not cross at any other point(s).
Therefore, correct option is B. Yes the graph passes the vertical line test.