In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D". 
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Question: [header] How to calculate a light year [title] Define the light year. [step] A light year is a measure of distance equal to how far light travels in one earth year. Because distances across the universe are so large, astronomers use light years. <sep> (A) However, they can also be determined by dividing by a distance. [substeps] Some light years are used year-round. (B) For light year 2014, the main determiner is the sun. In the light year, the world is filled with light bulbs. (C) Without light years, discussing the distance between two stars would require the use of large, unruly numbers. [substeps] Another measure of distance you may come across when learning astronomy is the parsec. (D) [substeps] There are two kinds of light years: day and night. The two types of light years are known as night and day.

Answer: C


Question: A man walks into a room. the man <sep> (A) is then sitting at a table, taking out sock remotes and tools. (B) begins to smooth plaster on the wall. (C) twists the objects made from pieces of wood. (D) is dozing and waking with his arms outstretched.

Answer: B


Question: The two people paddle from the left and pass a line of bushes in front of a mountain. the two people <sep> (A) are sitting down while the other man pulls the canoe behind the left of him. (B) then paddle further away from the mountain and closer to the middle of the body of water. (C) are seen riding a motor boat through a forest. (D) are walking on the beach, each holding their surfboard, going slowly, and changing their positions from one side of the beach to the other.

Answer:
B