You are presented with the quiz "What do refrigerators do?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "keeping food cold is used for keeping food fresh" and "refrigerators are suppose to add coldness to the food inside of it". So, what's the best answer to the question?

Options are:
[i] walk dogs
[ii] lowered energy cost
[iii] adding heat
[iv] hold gloves
[v] Decrease bodily water
[vi] make air
[vii] keep food fresh
[viii] staying warm
The answer is:
[vii]