You are presented with the question "Mammals conserve body heat with what that produce thickness and colors?" and the following answer choices: 
- sweating
 - Exfoliation
 - properties
 - four limbs
 - a cuticle
 - follicles
 - dense
 - heat energy

Now knowing that mammals conserve body heat with their hair or fur and hair follicles are capable of producing hair of various thickness and colors, choose the best answer.


 

      follicles   