Given a fact, create a question that can be answered using the fact. Construct the question such that it is unambiguous, has a unique answer and the answer can be given using the fact.
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Question: Fact: sunlight contains ultraviolet light

Answer: Which promotes the creation of serotonin?


Question: Fact: a star is a source of light energy through nuclear reactions

Answer: A star produces light energy and heat because it has a variety of?


Question: Fact: natural gas is a source of heat by burning

Answer:
Many families survive the winter thanks to?