​ What are the relative minimum and relative maximum values over the interval [−4, 4] for the function shown in the graph?

Hi SJ!

In this graph, if you look between x=-4 and x=4,

You can tell than the graph's y value fluctuates. 

The problem asks you for when the y is the peaks relatively the highest, maximum

And when y is the peaks relatvely the lowest, minimum 

The answer you are looking for is c. 

I'm pretty sure, but I never did these problems before, can someone check my work?

Yes, I think that's correct! Well done, Gavin!