Fact 1: Feathers help birds fly and provide insulation.

Fact 2: Penguins rely on their feathers for insulation.

Given the two facts above, answer the question "What keeps penguins warm?" with the following options: 
- feathers
 - muscles
 - Blankets
 - Animal fur
 - staying warm
 - energy
 - blood
 - fur and fat


 

 feathers        