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

Fact 2: Winter is the coldest season.

Given the two facts above, answer the question "what do some animals grow thicker fur for staying warm during?" with the following options: 
- dry and hot
 - in the autumn season
 - dry conditions
 - coldest season
 - colder weather
 - When it's cold
 - subtropical
 - Under 32 degrees


 

    coldest season     