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: many chemical messengers that control body functions are proteins. 
Question: What are many chemical messengers that control body functions?
[A]: proteins.


[Q]: Fact: melting means changing from a solid into a liquid by increasing temperature. 
Question: what is increased to cause something to change from a solid into a liquid?
[A]: temperature.


[Q]: Fact: If an object is black then that object absorbs all visible energy. 
Question: If an object is what color, it absorbs all visible energy?
[A]:
black.