Fact 1: Arefrigerator is used for keeping food fresh for a long period of time.

Fact 2: Refrigerator is too cold.

Given the two facts above, answer the question "What keeps food fresh?" with the following options: 
- bacteria
 - sodium
 - lipids
 - cold
 - gas
 - sugar
 - cooled
 - dust


 

    cold     