Fact 1: Sonar is used to find the location of an object.

Fact 2: Sonar bounces sound waves off the bottom of the ocean.

Given the two facts above, answer the question "Doing what with sound waves off the bottom of the ocean is used to find the location of objects?" with the following options: 
- observe it
 - skipping them
 - Electrical energy
 - rolling them
 - focusing a lens
 - hopping them
 - bouncing them
 - reflecting light


 

       bouncing them  