If a Reflected Ray in Air at an Angle of Reflection

Multiple Choice

If a reflected ray in air at an angle of reflection of 60 $^{\circ}$ is totally polarized,what is the index of refraction of the reflecting material?

A) 1.50
B) 2.00
C) 1.73
D) 1.15
E) this angle is not possible for an incident ray in air