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: In the 60's people watched on TV while for the first time people walked on (A) a high rooftop in a major city (B) a satellite without much air in our solar system (C) the edge of a cliff in the mountains (D) a beach in Brazil

A: B
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Q: Which of the following most likely led to certain rocks having less friction? (A) a babbling brook (B) people (C) a light wind (D) money

A: A
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Q: Tree rings can (A) indicate how often the tree needs pruning (B) tell you what year a tree was planted (C) tell you how tall a tree is (D) indicate the year the tree will die

A:
B
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