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

Q: Fires, mainly caused by lightning, are a natural disturbance in temperate grasslands.

A: Fires, mainly caused by what, are a natural disturbance in temperate grasslands?
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Q: Group 16 is called the oxygen group.

A: Group 16 is called what?
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Q: A grain of pollen can be described as a tiny male gametophyte enclosed in a tough capsule.

A:
What can be described as a tiny male gametophyte enclosed in a tough capsule?
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