The correct answer is option 4: more than one angle of incidence.
When a ray of light passes through a transparent glass plate, it undergoes both reflection and refraction. The angle of incidence is the angle between the incident ray and the normal to the surface of the glass plate.
If the angle of incidence is zero degrees or 90 degrees, then the reflected and refracted rays will not be perpendicular to each other. In these cases, the angle between the reflected and refracted rays will either be zero degrees or 180 degrees, but not 90 degrees. Therefore, option 1 and option 2 are incorrect.
When the angle of incidence is such that the reflected and refracted rays are perpendicular to each other, it is known as the angle of incidence for perpendicular rays. This can occur at multiple angles of incidence. Hence, option 3 is incorrect.
Therefore, the correct answer is option 4: more than one angle of incidence. The reflected and refracted rays can be perpendicular to each other at multiple angles of incidence.