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: An acorn growing into an adult tree will take the longest time to observe.

Answer: Which of these will take the LONGEST time to observe?


Question: Collision theory states that chemical reactions occur when atoms, ions, or molecules collide.

Answer: What states that chemical reactions occur when atoms, ions, or molecules collide?


Question: Sexual reproduction with gametes and fertilization produces diploid sporophyte.

Answer:
What does sexual reproduction with gametes and fertilization produce?