Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: Control rods play an important role in the modulation of the nuclear chain reaction.

Answer: What play an important role in the modulation of the nuclear chain reaction?

Question: Tornadoes can occur in any.

Answer: At what time of the year can tornadoes occur?

Question: Process of desalinization helps provide cleaner water for agriculture.

Answer:
Which process helps provide cleaner water for agriculture?