Answer:
A
Explanation:
To figure out whether a graph is a function, you need to use the line test. The line test is where you pass a vertical line over the graph. If the vertical line crosses the graph more than once, the graph is not a function. You can use your pencil as a vertical line.
Graph 1 is not a function because the vertical line will cross the graph twice.
Graph 2 is a function because the vertical does not cross the graph twice.
Graph 3 is not a function because the vertical line will cross the graph twice.