Question

_______ is an optical filter that passes light of a specific polarization and blocks waves of other polarizations.

a. Index of refraction
b. Laser
c. Polarizer

Answer 1

I’m not 100% sure but C. Would make sense

Answer 2

This filter picks out a specific polarization, so it makes a lot more sense to call it a polarizer than anything else. (C)

This question is a lot like asking "What color is an orange ?".