Why is an echo weaker than the original

Question

sound?
1. The echo has a shorter wavelength than
the original sound due to the reflection.
2. The echo has a smaller amplitude than
the original sound because sound spreads and
its intensity decreases with distance.
3. The echo has a longer wavelength than
the original sound due to the reflection.
4. The echo has a higher frequency than the
original sound due to the reflection.

Answer 1

kkkn

Answer 2

nfwbhr3bq

Answer 3

Answer is number 3