Fact 1: Afirecracker converts chemical energy into sound.

Fact 2: Energy is generated by sound waves.

Given the two facts above, answer the question "What can convert chemical energy into audible waves?" with the following options: 
- a flashlight
 - electrically
 - animals
 - a firecracker
 - power stations
 - sensory neurons
 - x-ray
 - electrical light


 

    a firecracker     