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: How does erosion impact a river? (A) enlargening (B) warming (C) heightening (D) shrinking

Answer: A

Question: A man will most likely be unable to see if he gets lost in (A) a dense forest (B) a long river (C) a desert (D) a mountain

Answer: A

Question: What slows down the transfer of heat? (A) a wooden wall (B) the wind (C) the sun (D) light rays

Answer:
A