an echo is an example of sound wave\na diffraction.\nb interference.\nc reflection.\nd refraction.
an echo is an example of sound wave\na diffraction.\nb interference.\nc reflection.\nd refraction.
Answer
Brief Explanations:
An echo occurs when a sound wave hits a surface and bounces back. This is the definition of reflection. Diffraction is the bending of waves around obstacles. Interference is the combination of two or more waves. Refraction is the bending of waves as they pass from one medium to another.
Answer:
C. reflection