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: Seedless and seed are the two divisions of vascular plants.

Answer: What are the two divisions of vascular plants?


Question: A crater can usually be found on the top of composite volcanoes.

Answer: A crater can usually be found on the top of what kind of volcanoes?


Question: Matter that mechanical wave energy can only travel through is medium.

Answer:
What is the name of matter that mechanical wave energy can only travel through?