You are presented with the question "What has a positive impact on an animal's survival?" and the following answer choices: 
- human hunting
 - echolocation
 - peachleaf willow
 - a lack of human aid
 - four limbs
 - a band aid
 - sensory neurons
 - genetic diversity

Now knowing that better senses have a positive impact on an animal 's survival and dolphins have an additional sense called echolocation, choose the best answer.


 

  echolocation       