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: Human facial expressions can communicate emotions.

Answer: What can human facial expressions communicate?


Question: Municipal type of pollution comes from sewage, storm drains, septic tanks, boats, and runoff from yards.

Answer: What type of pollution comes from sewage, storm drains, septic tanks, boats, and runoff from yards?


Question: Composition reaction type of reaction causes two substances to combine to make a single substance.

Answer:
What type of reaction causes two substances to combine to make a single substance?