Fact 1: Mammals conserve body heat with their hair or fur.

Fact 2: Mammals include squirrels, muskrats, opposums, and deer.

Given the two facts above, answer the question "What conserves body heat with its fur?" with the following options: 
- dogs
 - naked mole rats
 - shrews
 - humans
 - fish
 - deer
 - bats
 - whales


 

      deer   