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

[Q]: statement: mammals require food in order to run, question: What do mammals require to run?
[A]: food


[Q]: statement: a beak is used for catching maggots by birds, question: What do birds use a beak to catch?
[A]: maggots


[Q]: statement: muscles contracting cause a person's arm to straighten, question: What causes a person's arm to straighten?
[A]:
muscles contracting