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: Virtually all aquatic organisms depend directly or indirectly on protists for food.

Answer: Virtually all aquatic organisms depend directly or indirectly on what for food?

Question: Macroevolution happens when forces of evolution work over a long period of time.

Answer: What happens when forces of evolution work over a long period of time?

Question: Mutations in regulatory genes that normally control the cell cycle cause cancer.

Answer:
Mutations in regulatory genes that normally control the cell cycle cause what?