Final answer:
Vertically opposite angles are always equal. Therefore, the vertically opposite angle of 71° is also 71°.
Step-by-step explanation:
In Mathematics, when two lines intersect each other at a point, the opposite angles formed are called vertically opposite angles. The crucial property of these vertically opposite angles is that they are always equal. So if one angle measures 71°, the vertically opposite angle to it is also 71°.
To answer your question specifically, the measure of the vertically opposite angle of 71 degrees is (D) 71°.
Learn more about Vertically Opposite Angles