Question

If lines are perpendicular, what do you know about the angles at which they intersect?
A. They are parallel angles.
B. They are adjacent angles.
C. They are vertical angles.
D. They are right angles.

Answer 1

Meaning of perpendicular- at an angle of 90° to a given line, plane, or surface:

Answer 2

Exactly. So a right angle is just another name for a 90 degree angle. So it will be D.