Answer:
A
Explanation:
In the graph shown, no two y values share an x value. If you were to pass a vertical line through it at any point, it would only intersect it once, which makes it a function.
Many x values in the graph share y values; if you were to pass a horizontal line through it, it would intersect it more than once at certain points, which makes it NOT one-to-one.
This means that the answer is A: This is the graph of a function, but it's not one-to-one.