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

Q: Water and humidity is the critical factor for the survival of segmented worms.

A: What is the critical factor for the survival of segmented worms?
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Q: Climate map type of map would show average temperatures and rainfall.

A: What type of map would show average temperatures and rainfall?
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Q: Reduced family size is the key to the demographic transition.

A:
What is the key to the demographic transition?
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