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". 

Q: [header] How to polish rocks [title] Choose the right rock. [step] You can polish any stone you wish, but there are certain characteristics of a stone that will make it easier to polish. If you want an easy stone to polish, pick a somewhat softer stone like onyx, limestone or calcite. <sep> (A) [substeps] You can polish diamond, granite or ceramic stones by cutting thin pipe holes or inserting dry mortar into one side of each hole. Look for a stone that resembles a diamond, but not necessarily a diamond. (B) Otherwise, a smoother, more pumice-like stone will be more difficult to polish. [substeps] Emeralds and equilateral manganese are both excellent mineral polishes. (C) Stones that are very hard will take a much longer time to polish. However, though hard rocks take a long time to sand, they yield more shine than softer rocks. (D) Softer rocks will actually work more well, and might look better to polish very old stones, but brighter stones tend to chip quicker. [substeps] Rubies, sapphires, and emerald are good options.

A: C
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Q: A room is shown with an acoustic guitar lying across a beige sofa and a stone art piece in front of the sofa with rocks in it. a person, face unseen , <sep> (A) is standing in front of the rock wall with canvas in front of him and paints on a pallet. (B) begin to play the guitar and an image of a man teaching him how to play while he's playing backs into her music room and onto a white screen, not a person else. (C) holds a lit cigarette and the approached to lift up the guitar in a lounging pose. (D) approaches the sofa and picks up the guitar.

A: D
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Q: [header] How to gain that much required sense of self confidence (girls ) [title] Make a list of all dreams and aspirations. [step] Make a list of present and future aspirations whether it be just scribbling something on a scrap piece of paper. This, in itself, is a step-by-step process that you personally want to accomplish. <sep> (A) [substeps] Taking a step back from personal ambitions and coming up with a list of things you want to accomplish can help you walk away with a clear head. [title] Keep yourself bogged down in all things. (B) Remember that there is no limit to your dreams, they can be infinitive: never believe that your goal is impossible. There is no deadline (you can do within your own time). (C) Not every dream and vision will win you much-needed acceptance-that is, even if it doesn't exactly match your wants. Keep your list of things you want to achieve as you make changes. (D) [title] Accept your limitations, but keep doing what is right! [title] Don't overanalyze yourself. [step] Things happen to everyone and not the same people.

A:
B
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