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 relieve constipation after surgery [title] Use a stool softener. [step] One of the first medications to try if you're feeling constipated is a stool softener. These are easy to find over-the-counter and can help get you back on track. <sep> (A) [substeps] The way that stool softeners work is that they draw water into your stool from your intestines. This makes your stool softer and easier to pass. (B) [title] Take 600ml of stool softener before a meal. [step] Most stool softeners kill the production of prostaglandins. (C) [substeps] One good option for relieving constipation at the time of surgery is a stool softener. While stool softeners do provide temporary relief from constipation, they are expensive and will often disappoint you. (D) These medications are named for their antioxidant properties, which help reduce diarrhea and keep your stools from becoming irritated. [substeps] Remember that: the next time you're using an over the counter stool softener treatment, be sure to follow the dosing instructions.
Example Output: A

Example Input: [header] How to make black coffee [title] Purchase freshly roasted, whole bean coffee. [step] If you can't purchase it directly from the roaster within a week or so of it being roasted, opt for a vacuum-sealed bag from a reputable national coffee-bean roaster. [title] Purchase your own coffee grinder, or grind it in the store. <sep> (A) [step] If possible, choose a burr grinder in place of a normal blade grinder. For best results, grind the coffee fresh right before brewing each day. (B) [step] Grind coffee beans in the near-black zone of a coffee grinder. You can use either a regular-size grinder or a pre-grind grinder to grind your coffee. (C) [step] Modern coffee grinders have drawbacks, as they require higher temperatures to make purified coffee. Where possible, purchase one that comes pre-boil. (D) [step] Print it onto a piece of paper, remove the lid from the coffee grinder, and grind the coffee beans in the machine's center. [title] Unplug the coffee grinder and plug it into the wall outlet.
Example Output: A

Example Input: [header] How to try compassion meditation [title] Start in a comfortable place. [step] To start compassion meditation, you should be in a quiet, calm environment. This may be a room in your home or a relaxing place outside. <sep> (A) Here are some good places to start : [substeps] The living room, your bedroom, or any place where you are alone. You may also try the bathroom or any other comfortable space you have. (B) Make sure you are not disturbed by others. Get into a comfortable position that you can relax in. (C) Try to find a spot where you can focus fully on your breathing and your thoughts. [substeps] Place your feet on a table in front of you and a block of support behind your back. (D) Find a quiet space that has little to no noise but no distractions. [substeps] Try sitting on a chair or in a lying position that will not make noise or distraction you from your meditation.
Example Output:
B