Solution:Concept- Angles are measured in degrees. There are 360 degrees in a circle. A right angle, for instance, is 90 degrees. Ninety degrees would be expressed as 90° since the sign for a degree is °. The radian is yet another angle measurement unit.
One right angle is equal to, Using the unitary method to calculate the degree.
Given is that one right angle
1) One right angle
2) Two right angles
3) Three right angles =
4) Four right angles
Hence, the correct option is 3) .