Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Q: Gardasil is the vaccine to prevent infection of hpv.

A: What is the vaccine to prevent infection of hpv?
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Q: Tornadoes can occur in any.

A: At what time of the year can tornadoes occur?
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Q: The voyager 1 spacecraft visited saturn in 1980.

A:
What planet did the voyager 1 spacecraft visit in 1980?
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