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: using a car causes pollution

A: Which form of travel causes the most pollution?
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Q: Fact: rainfall is the amount of rain an area receives

A: What will be more available in an area when rainfall increases?
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Q: Fact: using a car causes pollution

A:
Which form of travel causes the most pollution?
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