Fact 1: Feathers help birds fly and provide insulation.

Fact 2: Penguins keep warm with layers of insulation.

Given the two facts above, answer the question "Feathers help birds fly and what?" with the following options: 
- staying warm
 - keep warm
 - Absorb light
 - allow growth
 - keep birds
 - protect them
 - keep cool
 - keep grounded


 

  keep warm       