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: Protists are thought to be the oldest eukaryotes.

Answer: What is thought to be the oldest eukaryotes?


Question: Bile acids, needed to emulsify lipids, are stored in the body in the gallbladder.

Answer: Where are bile acids, needed to emulsify lipids, stored in the body?


Question: Learned behavior is adaptive because they are flexible, capable of changing if the environment changes.

Answer:
What kind of behaviors are adaptive because they are flexible, capable of changing if the environment changes?