Fact 1: Keeping food cold is used for keeping food fresh.

Fact 2: Keep your food fresh, simple and as natural as possible.

Given the two facts above, answer the question "What is used to keep foods as simple and as natural as possible?" with the following options: 
- Energy
 - sodium
 - lipids
 - heat
 - RNA
 - cold
 - fibers
 - sugar


 

      cold   