In this task, you are given a multiple-choice question and you have to pick the correct option. Answer with option indexes (i.e., "A", "B", "C", and "D").

Q: What did some ancient societies use to reflect light? (A) wood (B) plants (C) clothing (D) rocks

A: D
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Q: an animal needs to burn complex carbohydrates to (A) stay up (B) move (C) sit (D) sleep

A: B
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Q: Something is coming out of clouds on a dark day, so it is likely (A) birds (B) dust (C) precipitation (D) angels

A:
C
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