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". 

Example Input: [header] How to remove hair from your throat [title] Try to swallow the hair. [step] If you suspect that you have one or two hairs stuck in your throat, try to just swallow them. The hair will travel through your digestive tract like food does and your body will excrete them. <sep> (A) Pass the hair around your mouth under your tongue until you see no more hairs. It's important that you close your mouth as tightly as possible so that the hairs don't come back. (B) Sucking in the hair will leave your throat full of the hair. If the hairs are stuck in your throat, then you might want to rub a cotton ball or toilet paper over your throat to help get rid of the hairs. (C) This will open up the glycerine lining in your throat and prevent anything from coming out. [substeps] Wait a few minutes to see if they're gone. (D) Your body will not break down the hair because it's made of keratin, a dense protein. [substeps] If it feels like the hair is long, see if you can use your clean fingers to pull the hair out of your throat.
Example Output: D

Example 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.
Example Output: C

Example Input: [header] How to turn forty gracefully [title] Set a realistic weight goal. [step] A realistic weight goal should be based on the body and limits of your current self, not the self you wish you had or the self you had twenty years ago. Your goal should be specific and measurable, and limited in time. <sep> (A) [substeps] For example, if you are 35 years of age and have an empty stomach, then set a goal to lose ten pounds in thirty years from now on. Keep in mind that you will not see the difference in yourself if you start getting older. (B) If you are unable to accomplish a current weight goal, you should also consider setting another goal, often known as a baptism goal. Baptism goals provide an answer to both your doubting thoughts and worried questions. (C) [substeps] For instance, a goal to lose twenty pounds is a good goal. A goal that is vague like " i want to get fit " is not measurable. (D) [substeps] For example, if you are looking to reduce your overall physical limits, you might set realistic weight goals. For example, you might set out to lose 30 pounds in one year and then lose 20 pounds in another year, and then lose 25 pounds within that year.
Example Output:
C