You are presented with the quiz "threatening behavior causes the what and hormones to flood the body" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "threatening behavior causes a fight-or-flight response in animals" and "hairs stand on end, the heart races and fight or flight hormones flood the body". 

So, what's the best answer to the question?


 

 heart to race          