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

Fact 2: Fresh food is good.

Given the two facts above, answer the question "What appliance can keep food good a long time?" with the following options: 
- toaster
 - Fuel cells
 - Cooking
 - a hydraulic system
 - an electric stove
 - oven
 - refrigerator
 - vacuum cleaner


 

       refrigerator  