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

Q: Mechanical waves term describes waves that travel through matter.

A: What term describes waves that travel through matter?
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Q: Exotic species are also called invasive species because they threaten other species.

A: Why are exotic species also called invasive species?
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Q: Muscle groups are controlled by the motor cortex .

A:
Muscle groups are controlled by what mechanism?
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