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 white screen appears with colorful special effects that include a child's face a flying blue butterfly and colorful words that read "healthy child healthy world healthychild", another white screen appears with the words "healthy child tv healthy bytes". a woman <sep> (A) then appears wearing a front yard apron and proceeds to dodge a fly that flies after her. (B) is standing in a kitchen, and she begins to rub ingredients into cake pans, which she dumps onto the pan. (C) is now standing in a kitchen, words on the screen say her name is jennifer taggart and she's an eductional program specialist, and she's talking the whole time while demonstrating on how to measure ingredients and then she pours them into a clear glass bottle through a funnel. (D) is then shown painting nails and jacket or clothing on a blue paper piece styled with colors that begins with red and blue.

A: C
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Q: The people are shown playing the drums using wooden drumsticks. There are also people behind them playing golden cymbals. after a while <sep> (A) the drum is played and then everything stops. (B) , she stops playing the drums and turns to the audience. (C) , the video ends giving way to the woman marching down the street with her guitar. (D) they all stop playing and stand silently.

A:
D
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