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

[Q]: For to synthesize glycogen purpose does liver use the excess carbohydrate.
[A]: For what purpose does liver use the excess carbohydrate?


[Q]: Most of the gray matter is on the surface of the brain, surrounding white matter.
[A]: Most of the gray matter is on the surface of the brain, surrounding what other type of matter?


[Q]: The abundance of water makes the earth habitable for humans.
[A]:
What makes the earth habitable for humans?