Fact 1: If food is not immediately used by the body for energy then that food will be stored for future use.

Fact 2: Body fat is stored energy.

Given the two facts above, answer the question "What not digested is used as energy storage?" with the following options: 
- RNA
 - Urea
 - fat
 - glucose
 - carbohydrates
 - food
 - protein
 - DDT


 

   fat      