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: The things that are the smallest agents of disease are usually considered to be nonliving. 
Question: The things that are the smallest agents of disease are usually considered to be what?
answer:
nonliving.


question:
Fact: Humans have collected and grown fungi for food for thousands of years. 
Question: What have humans collected and grown as food for thousands of years?
answer:
fungi.


question:
Fact: High pressure systems are the result of sinking air. 
Question: What causes high pressure systems?
answer:

sinking air.