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

Q: Stopping a car can cause skidding.

A: What can stop a car cause?
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Q: The intentional release of smallpox is considered bioterrorism.

A: What is the intentional release of smallpox considered?
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Q: bone density decreases when osteoclasts are more active than osteoblasts

A:
What is more active than osteoblasts?
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