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: Dig a well allows people to access water in an aquifer that does not flow from a spring or a geyser.

Answer: How can people access water in an aquifer that does not flow from a spring or a geyser?


Question: The cardiovascular system in the human body consists of the heart, a network of blood vessels, and blood.

Answer: Which system in the human body consists of the heart, a network of blood vessels, and blood?


Question: Most of the earth's freshwater is in the form of frozen.

Answer:
In what form is most of the earth's freshwater?