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: The discovery of ribozymes nullified the idea that all biological catalysts are proteins.

Answer: What nullified the idea that all biological catalysts are proteins?


Question: Radioactive decay can give off energy and particles.

Answer: Radioactive decay can give off energy and what else?


Question: Theevolution by natural selection theory explains how populations of organisms can change over time.

Answer:
Which theory explains how populations of organisms can change over time?