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").
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Question: A tree must depend upon, for its support (A) A large fibrous mass (B) plants on the forest floor (C) the wooden welfare state (D) massive redwoods on the backs of turtles

Answer: A

Question: Someone is driving at night. The day was warm, but now the night is cool, and there is a lot of mist that is difficult to see through. The mist is prevalent because (A) humidity from the day condensed as night progressed (B) warm air is usually found in daytime (C) it is always misty at night (D) the cool air makes everything feel warm

Answer: A

Question: Hummingbirds gather nectar using their (A) bills (B) wings (C) hands (D) feet

Answer:
A