You are presented with the question "What can our ears detect?" and the following answer choices: 
- extremely high frequencies
 - matter vibrating
 - population movement
 - extremely high-pitched sound
 - electromagnetic energy
 - matter's height
 - sensory neurons
 - rays or beams

Now knowing that matter vibrating can cause sound and when the waves pass our ears, a sound is detected, choose the best answer.


 

  matter vibrating       