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

Q: Most ferns produce the same type of spores and are therefore called homosporous.

A: Most ferns produce the same type of spores and are therefore called what?
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Q: Temperature and ph level are important in the activity of an enzyme.

A: Temperature and what other environmental factor are important in the activity of an enzyme?
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Q: High gravity explains the spherical shape of ceres, once thought to be the largest asteroid.

A:
What explains the spherical shape of ceres, once thought to be the largest asteroid?
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