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: 600 million many years ago may the earliest fungi have evolved.

Answer: How many years ago may the earliest fungi have evolved?


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

Answer: What term describes waves that travel through matter?


Question: Sexual reproduction process is a cause of variation in a species.

Answer:
Which process is a cause of variation in a species?