You are presented with the question "blowing and causing air to vibrate makes what" and the following answer choices: 
- expand
 - evaporate
 - kinetic energy
 - waves
 - Energy.
 - combine
 - loud noise
 - energy

Now knowing that blowing air into a whistle causes air to vibrate inside the whistle and if the persist, blow a whistle loudly into the mouthpiece, choose the best answer.


 

       loud noise  