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

Q: Volvox sphere has a distinct front and back end.

A: What has a distinct front and back end?
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Q: Fermat's principle states that light will always take the path of the least amount of time.

A: Fermat's principle states that light will always take the path of least amount of?
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Q: Bacteria are the most numerous species on the planet.

A:
What is the most numerous species on the planet?
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