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: Combustion reaction occurs when a substance reacts quickly with oxygen.

Answer: What occurs when a substance reacts quickly with oxygen?


Question: Antibodies recognize and combine with harmful materials, including both toxic chemicals and invasive microorganisms.

Answer: Which proteins recognize and combine with harmful materials, including both toxic chemicals and invasive microorganisms?


Question: Cancer is caused by mutations, which can be caused by pathogens, chemicals, or radiation.

Answer:
Cancer is caused by mutations, which can be caused by pathogens, chemicals, or what else?