The bending of a wave as it moves around an obstacle or passes through a narrow opening is called
interference
reflection
diffraction
refraction

Diffraction

Explanation:

Diffraction is a phenomenon of light that consists of light being able to pass through obstacles or through openings. In the case of a small opening, light can pass through it and the opening becomes a new source of light.

This phenomenon is described by the wave properties of light, and explains why light scatters.

An application of diffraction is the diffraction gratings, which have many openings in such a way that when light passes through them, each one becomes a light source causing interference (interference and diffraction are sometimes related but they are not the same) and the separation of light into colors.

In summary, the bending of a wave as it moves around an obstacle or passes through a narrow opening is called diffraction