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

[EX Q]: Oil is the most commonly used source of energy in the world.
[EX A]: What is the most commonly used source of energy in the world?

[EX Q]: The majority of arthropods live on land.
[EX A]: Where do the majority of arthropods live?

[EX Q]: Water supply contamination type of contamination causes almost 90% of diarrheal disease worldwide.
[EX A]:
What type of contamination causes almost 90% of diarrheal disease worldwide?