You are presented with the question "What sort of behavior can cause fight-or-flight responses?" and the following answer choices: 
- hyperthyroidism
 - aggressive
 - hormones
 - humans
 - bullfrogs
 - hypothyroidism
 - similar
 - some mammals

Now knowing that threatening behavior causes a fight-or-flight response in animals and if a pony feels threatened it can respond with aggressive behavior, choose the best answer.


 

  aggressive       