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: Glaciers deposit their sediment when they melt.

Answer: When do glaciers deposit their sediment?


Question: The cells in the follicle undergo physical changes and produce a structure called a corpus luteum.

Answer: The cells in the follicle undergo physical changes and produce a structure called a what?


Question: Nitrogen increases protein production in plants best explains the importance of nitrogen in the cycling of energy and matter.

Answer:
Which best explains the importance of nitrogen in the cycling of energy and matter?