Question

what behavior does a sound wave have when it echos? reflection refraction absorption transparent

Explanation:

An echo occurs when a sound wave hits a surface and bounces back, which is the definition of reflection (wave bouncing off a surface). Refraction is bending of waves, absorption is wave energy being taken in, and "transparent" relates to light transmission through materials, not sound echo. So the sound wave behavior during an echo is reflection.

Answer:

Reflection