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 clean rubber boots [title] Wipe away light dirt and grime. [step] If your boots aren't especially dirty, you can usually clean them easily with a damp cloth. To prevent dirtiness from building up on your boots and causing longer cleaning times, do this after each time you use your boots. <sep> (A) Before handling an object or stepping on something wet, make sure you wipe it away on a rag first. Use a mild soap and water to wipe off even the smallest traces of dirt. (B) [substeps] To increase the dirt fighting potential of your damp cloth, mix 1 tsp (5 ml) of dish soap with a gallon (1 l) of water. Douse your rag in this, and wipe down the boots. (C) [title] Grind three pounds (177 g) of dry powder on a coffee grinder. [step] The dry powder will help to transfer dirt and dust to the boots. (D) This will clear little dirt and grime off of your boots, leaving them looking brand new. [substeps] If your boots are already cleaned, you may need to consult a shoe store or partner to inspect them for a better cleaner.

Ex Output:
B

Ex Input:
A man demonstrates how to walk across and navigate a slackline in a grass courtyard in front of apartments. the man <sep> (A) demonstrates how to traverse a low brick fence on a residential street. (B) walks slowly across the slackline while talking and stopping to talk to passerbys. (C) stands on a slackline balancing himself with his arms before the clip cuts to him interviewing. (D) poles backward, glasses on and he begins to walk while holding the slackline while walking across the courtyard.

Ex Output:
C

Ex Input:
[header] How to be hopeful but realistic [title] Identify your values. [step] To get into a more hopeful state of mind, realize that your future is yours to take control of. You are in charge of deciding what you will achieve. <sep> (A) Instead of focusing on one specific goal-" become a better person. " you can identify your values by helping others figure them out. (B) [substeps] Think about what you want your life to be like in a year and realize that, with hard work, you are capable of making it happen. [title] Know that you are able to shape your life. (C) Instead of thinking, " i can't accomplish this, " pull yourself together and tell yourself, " yes, i can " or " i can succeed " rather than just judging yourself harshly. [substeps] Think about your own passions and find ways to make that clear in your own life. (D) [substeps] Just like you are in charge of appreciating the things you love, you are also in charge of how you will achieve it. The key to becoming optimistic is to realize that things you love have already been realized as successes or failures.

Ex Output:
B