You are presented with the question "What  can be used for communication by animals?" and the following answer choices: 
- electricity
 - energy
 - Telephones.
 - Vibrations.
 - Stuffed animals.
 - messengers
 - courtship
 - Cellular communication.

Now knowing that sound can be used for communication by animals and sound vibrations have different frequencies, choose the best answer.


 

    Vibrations.     