Use the graph to evaluate the step function at x =3

D

Step-by-step explanation:

To evaluate the value of the function at 3, draw vertical line and find the point of intersection of this line with the graph of the given function.

You can see that the vertical line has two common points with the graph: (3,5) and (3,7). The first point (3,5) is solid (filled), so this point belongs to the graph and it is the point of intersection. The second point (3,7) is open point (not filled), so this point does not belong to the graph, so it cannot be the point of intersection.

Hence,