Question

multiple-choice question
when waves hit a boundary they are ____.
reflected.
refracted.
diffracted.

Explanation:

When waves hit a boundary, reflection occurs as waves bounce back from the boundary. Refraction is the bending of waves when entering a different medium, and diffraction is the spreading of waves around obstacles or through openings. The key here is the interaction with a boundary causing the wave to bounce back, which is reflection.

Answer:

A. reflected.