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: If a planet becomes too hot, then it cannot maintain a balanced ecosystem. 
Question: If a planet becomes too hot, then it cannot maintain what?

A: balanced ecosystem.
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Q: Fact: A cactus stem is used for storing H20. 
Question: A cactus stem is used for storing what?

A: H20.
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Q: Fact: Strokes occur when clogged arteries prevent oxygenated blood from reaching the brain. 
Question: What happens when oxygenated blood doesn't reach the brain?

A:
a stroke.
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