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: Transient pseudopodia are temporary feet that protists have called.

Answer: What are temporary feet that protists have called?


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: The sun and the moon appear to be about the same size in the sky because the moon is smaller in diameter and is closer to earth than the sun.

Answer:
Which statement best explains why the Sun and the Moon appear to be about the same size in the sky?