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

Fact 2: Hair follicles are capable of producing hair of various thickness and colors.

Given the two facts above, answer the question "Mammals conserve body heat with what that produce thickness and colors?" with the following options: 
- sweating
 - Exfoliation
 - properties
 - four limbs
 - a cuticle
 - follicles
 - dense
 - heat energy


 

      follicles   