Answer: D. Right angle
Step-by-step explanation:
By definition a right angle is an angle that measures 90 degrees.
You can identified the following facts in the figure attached:
- There is a box in a corner (which is used to indicate a right angle).
- The bisector XY is perpendicular to the segment DE.
The facts above indicates that the angle formed measures 90 degrees, therefore, it is a right angle.
