Answer
The graph with a maximum value of $3$ is $f'(x)$ while the other is $f(x).$
Work Step by Step
By checking the behavior of one graph at the roots of the other, it can be decided which graph is which.
When the graph with a maximum value of 3 has a root, the other graph has a horizontal tangent; hence, the graph with maximum value of $3$ is $f'(x)$and the other is $f(x).$
