Given a statement and question, generate the answer to the question such that the answer is contained in the statement.

Q: statement: A person's arm straightens when muscles antagonistic to biceps contract, question: What straightens when muscles antagonistic to biceps contract?

A: arm
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Q: statement: Rabbits give birth to relatively large and mature infants, question: What gives birth to relatively large and mature infants?

A: Rabbits
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Q: statement: a thinning and weakening of bone is an affliction in which osteoclasts are more active than osteoblasts, question: What are more active than osteoblasts?

A:
osteoclasts
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