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: We can calculate a speed if we know a number of (A) gallons (B) millimeters (C) dollars (D) pounds

Answer: B

Question: A light is refracted when (A) it shines at a gem (B) it shines at a mirror (C) it reflects off a spoon (D) it reflects off a car

Answer: A

Question: Where would an archaeologist likely find an impression of an ancient footprint? (A) lying on the beach (B) under layers of dirt (C) on the surface of the moon (D) buried in a graveyard

Answer:
B