Fact 1: Threatening behavior by predators causes a porcupine to extend its quills.

Fact 2: Porcupines are in the rodent family.

Given the two facts above, answer the question "What extends something because of threatening behavior by predators?" with the following options: 
- influenza
 - chickenpox
 - A rodent
 - A primate
 - A treeshrew
 - fur and fat
 - A flying lemur
 - an object


 

   A rodent      