instruction:
Write a correct answer to the given question based on its associated fact. Make sure that your answer is contained in the associated fact. Don't be creative and introduce any new word that is not mentioned in the associated fact! Remember that the associated fact has been rearranged to form the question. So, the correct answer words must lie within the associated fact. The correct answer can be a word, phrase, or even a sentence.
question:
Fact: cell regeneration requires rest. 
Question: what requires rest?
answer:
cell regeneration.


question:
Fact: Something that grows in Mexico can be used for storing water. 
Question: What can be used for storing water?
answer:
Something that grows in Mexico.


question:
Fact: Boulders are formed in the mountains. 
Question: What can be formed in a mountain?
answer:

boulder.