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: Water and humidity is the critical factor for the survival of segmented worms.

Answer: What is the critical factor for the survival of segmented worms?

Question: The nuclear envelope is a double-layered plasma membrane like the cell membrane, although without membrane proteins.

Answer: The nuclear envelope is a double-layered plasma membrane like the cell membrane, although without what?

Question: When performing anaerobic exercise, your muscles work against resistance.

Answer:
When performing anaerobic exercise, your muscles work against what?