Why can gamma rays pass through or penetrate solids?

Question

A. gamma rays have low mass.

B. gamma rays have high mass.

C. Gamma rays have low velocity.

D. Gamma rays have high velocity.

Answer 1

Gamma rays are photons, which have no rest mass, so that eliminates answers (A) and (B).  Photons travel at the speed of light, which is the speed limit of the physical universe, so that eliminate answer (C).  Given the above choices, answer (D) is the best answer, although there is more to it than just velocity.