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". 

Input: Consider Input: [header] How to get rid of migraines [title] Learn all you can about migraines. [step] Nobody knows exactly what causes migraines. A lot of research has gone into the exact cause of migraines, but with little success. <sep> (A) People who experience migraines regularly have been having regular consultations with doctors and they still don't know what is causing them. Anything you experience requires some much-needed research or hypnosis to rule out any medical issues or underlying conditions. (B) Migraines result from a lack of sensory focal points or groups. They occur in fewer than three brain groups. (C) Just finding out what causes them will give you some tips on dealing with them. [substeps] Most people develop migraines because they have no symptoms or aren't able to respond to stimuli. (D) It is generally agreed upon that the trigeminal nerve plays a role in migraine pain. The trigeminal nerve is a cranial nerve that facilitates a major pain pathway.

Output: D


Input: Consider Input: We see a man teaching others to sharpen a knife in a butcher shop. The man wets the sharpening stone. Two men in the back laugh at something. the instructor <sep> (A) shows us a basket of pennies. (B) checks the knives and uses the sharpened knife to sharpen a one. (C) uses a sharpening rod for the knife. (D) puts a paper in the sink.

Output: C


Input: Consider Input: [header] How to prevent tartar [title] Brush your teeth at least twice a day. [step] In order to remove plaque from your teeth, and in turn prevent tartar from developing, it's important to brush your teeth. Brushing twice a day is recommended to keep plaque and tartar at bay. <sep> (A) Brush as much as twice a day depending on your current regimen. [substeps] Brush the outside surfaces of your teeth to break up plaque and tartar. (B) [substeps] Typically, you should brush your teeth in the morning when you get up and in the evening before you go to bed. However, pick a brushing schedule that works for you and stick to it. (C) [substeps] When brushing, use gentle circular motions that brush the gums and edges. Focus on areas that are clogged with tartar. (D) [substeps] Using a toothbrush or a regular brush, brush your teeth twice a day. Double your brushing schedule each time you brush your teeth to help eliminate plaque.


Output: B