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: Present-day plants that have a complex vascular tissue system are called vasuluar plants.

Answer: Present-day plants that have a complex vascular tissue system are called what kind of plants?

Question: Glaciers deposit their sediment when they melt.

Answer: When do glaciers deposit their sediment?

Question: Vertebral column makes up the core of the endoskeleton.

Answer:
What makes up the core of the endoskeleton?