In this task, you are given a sentence and a question, you would be asked to create the answer which is contained in the sentence provided.

Q: Sentence: Mutation is essential in order for evolution to occur because it increases genetic variation and the potential for individuals to differ. Question: What phenomenon is essential in order for evolution to occur because it increases genetic variation and the potential for individuals to differ?

A: mutation
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Q: Sentence: Chemical energy is stored in the atom bonds. Question: Where is chemical energy stored?

A: atom bonds
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Q: Sentence: Muscles need stimulus to contract. Question: What do muscles need to contract?

A:
stimulus
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