What term describes the phenomenon where a ray of light is turned back into the incident material after striking a surface?

The term that describes the phenomenon where a ray of light is turned back into the incident material after striking a surface is reflection. When light encounters a surface, a portion of it may bounce back instead of passing through or being absorbed by the surface, which is the fundamental principle of reflection. The angle at which light hits the surface (angle of incidence) is equal to the angle at which it reflects away from the surface (angle of reflection), adhering to the law of reflection.

In contrast, refraction involves the bending of light as it passes from one medium to another, leading to a change in speed and direction. Diffraction refers to the bending of waves around obstacles or through openings, resulting in interference patterns. Absorption is the process in which the energy of light is taken up by the material, preventing it from being reflected or transmitted further. Therefore, reflection is specifically about the returning of light into the medium from which it originated upon interaction with a surface, making it the correct term in this context.