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.

[Q]: Fact: When heat passes through metal, that metal expands. 
Question: What happens to metal when heat passes through it?
[A]: It expands.


[Q]: Fact: mitosis is how organisms grow and repair themselves. 
Question: What is how organisms grow and repair themselves?
[A]: mitosis.


[Q]: Fact: Infancy is the period of most rapid advancement. 
Question: What is the period of most rapid advancement?
[A]:
infancy.