You are presented with the question "What does a radio use to make vibrations?" and the following answer choices: 
- waves
 - rays or beams
 - a battery
 - an object
 - barrel-shaped
 - nerves
 - Loud noises
 - it needs them

Now knowing that aradio converts electrical energy into vibrations and electric energy is stored in batteries, choose the best answer.


 

   a battery      