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: A tone is made when a hammer makes contact with (A) a waterfall (B) air (C) an solid object (D) a log

A: C
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Q: You can work longer when (A) Autumn changes to Winter (B) spring changes to summer (C) tree leaves start falling (D) the first snow starts falling

A: B
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Q: Some bacteria are beneficial and some bacteria (A) cause droughts (B) cause thriving populations (C) cause rosacea (D) cause upset stomach

A:
D
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