To solve this problem, we need to recall the definition of a right angle.
A right angle is defined as an angle that measures exactly 90∘. This is a standard definition found in geometry, describing an angle formed by the intersection of two perpendicular lines.
Given the multiple-choice options, we need to identify which one corresponds to a right angle:
- A right angle measures 90∘.
Let's examine the provided choices:
- Angle of 180°.
- Minor angle of 90°.
- Angle of 90°.
- Angle greater than 90°.
Choice 3, "Angle of 90°," directly matches the definition of a right angle.
Therefore, the correct answer is Angle of 90°.