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". 

Ex Input:
[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.

Ex Output:
C


Ex Input:
[header] How to learn to speak afrikaans [title] Take an introductory afrikaans class. [step] Enroll in an introductory class at a local community college, or at a language learning center. You can also find organizations dedicated to language learning online. <sep> (A) Online classes are convenient because you can learn at your own pace. [substeps] Taking an introductory class will help you develop a solid foundation in the language. (B) Online afrikaans are very easy to learn, and they are easy to translate. [substeps] You can get an introductory afrikaanic class at a language learning center. (C) [substeps] The language federation at the children's development center maintains a directory of all language learning organizations across all states. You can also find native afrikaans reading online through the font bar at the bottom of the page or clicking " language group " in the top right corner. (D) [title] Immerse yourself in afrikaans from a young age. [step] Select a language you are receptive to and that you truly understand.

Ex Output:
A


Ex Input:
We see a green swirling opening scene. an eye doctor <sep> (A) talks as we cut to scenes of a woman putting her contacts in. (B) starts speaking then we see the body of water. (C) is outdoors where he is helping a boy walk through obstacles. (D) then speaks with two women as a man rinses his face in shaving cream.

Ex Output:

A