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: Smaller size of ring will a summer drought cause in a tree.

Answer: What size of ring will a summer drought cause in a tree?

Question: The human eye detect can detect three colors of light.

Answer: How many colors of light can the human eye detect?

Question: Covalent compounds form individual molecules rather than crystals.

Answer:
Covalent compounds form individual molecules rather than what?