Fact 1: Some animals' fur grows thicker for staying warm in the winter.

Fact 2: Winter is snow, winter is Christmas.

Given the two facts above, answer the question "Why do some animals grow thicker fur around Christmas in the Northern hemisphere?" with the following options: 
- overheat
 - protect them
 - stay warm
 - climate
 - adding heat
 - warm other animals
 - stay cool
 - sun's heat


 

   stay warm      