Fact 1: Blowing air into a whistle causes air to vibrate inside the whistle.

Fact 2: Sounds are vibrations in air.

Given the two facts above, answer the question "What creates sounds?" with the following options: 
- energy of moving objects
 - chemical messengers
 - the body's largest organ
 - peace
 - Thinking hard
 - Blowing a whistle
 - Electrical energy
 - death


 

      Blowing a whistle   