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.

[EX Q]: Fact: Digestion is the process of breaking down food proteins into energy or heat. 
Question: What is the process of breaking down food proteins into energy or heat?
[EX A]: digestion.

[EX Q]: Fact: Viruses are viewed by illuminating electrons. 
Question: What of the following can only be viewed by illuminating electrons?
[EX A]: viruses.

[EX Q]: Fact: most living things consume and are consumed by more than one species. 
Question: what consumes and are consumed by more than one species?
[EX A]:
most living things.