Answer
The graph represents a function because it passes the vertical line test, which means there is only one $y$ value for every $x$ value.
Work Step by Step
According to the vertical line test, if we draw a vertical line through any point on the graph, the line will only go through one point on the graph, meaning that there is only one $y$ value for every $x$ value.
Note that every vertical line will pass through only one point on the given graph
Thus, the graph represents a function.
