Answer
It is one-to-one (at least if the domain is restricted to what is shown on the graph).
Work Step by Step
This function is one-to-one if we restrict the domain to what is presented on the graph because this function passes the horizontal line test - whatever horizontal line you draw, it will intercept the graph of the function at most once so there is one-to-one correspondence between $x$ from the domain and $y$ from the range.