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: [header] How to start salary negotiation [title] Look up salary information for similar positions. [step] Before you develop your own range, you should have a general idea of the going rate in the industry. [substeps] Make sure you have a full understanding of the particular job being offered, including the exact responsibilities and expectations for someone in that role. <sep> (A) You'll need to do a lot of research to ensure you understand the expectations of that job so you can easily look it up to the perfect employer. The rate for each individual position is its own set of guidelines, so the application process should take some time. (B) In addition to assessing your capabilities, you should also know what the salary market expects of you. This will take into account your level of experience in the industry, as well as the demand for that position. (C) That will help you evaluate what the position is worth in other firms. Different companies may call similar positions by different names, so if you don't have an understanding of the full job description you won't know which other jobs compare with the one you've been offered. (D) You also will want to get a good understanding of whether or not higher salary is required for similar positions as the one you are looking at. To determine whether or not the position is state-specific, research the company's new hire contract and check for various requirements such as the recipient's income.

Answer: C

Question: [header] How to do an open turn in swimming [title] Swim towards the wall. [step] When you're on your last stroke of the butterfly or breaststroke, move your head to look straight down at the bottom of the pool. [substeps] Your last stroke should bring you about half a body length away from the pool wall. <sep> (A) You'll not hit the pool wall at this point. If you can also move or jump towards the wall, you're likely to land more powerfully on the water surface. (B) If you are more than half a body length from the wall, give an extra kick in the water to push yourself forward. [title] Extend your arms to reach for the wall. (C) If you use all of your body weight while swimming down the beautiful short distance, you'll trip backward and will risk losing your balance. Also remember that you are not swimming straight to the wall--you are swimming down it. (D) Practice the butterfly as close to the wall as possible without looking down at the bottom of the pool. Practicing in the reverse order of the butterfly and breaststroke can help ensure you don't miss any essential strokes while swimming around your current current group of swimmers.

Answer:
B