Given a fact, create a question that can be answered using the fact. Construct the question such that it is unambiguous, has a unique answer and the answer can be given using the fact.

Q: Fact: migration is when animals move to different locations in an annual cycle

A: Which phenomenon is studied about once annually?
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Q: Fact: an landfill is a source of pollution

A: Landfills can cause?
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Q: Fact: An example of playing a musical instrument is strumming a guitar string

A:
School children often play a musical instrument by?
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