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 treat your customer while serving them [title] When the customer approaches your till point, greet them nicely. [step] This means you should acknowledge the customer with eye contact. Say " hello " and smile. <sep> (A) [title] Apologise for any wait, no matter how short. [step] The customer might not understand why they have had to wait. (B) [substeps] Also greet them in a professional manner. Always state your name, address, and similar things. (C) Offer him or her a fresh drink once in awhile. [substeps] Remember to shake each customer's hand. (D) If you don't meet their smile they'll get bored and start saying no. To greet the customer again, do a brief " hi " and introduce them to your horde.

Output: A


Input: Consider Input: [header] How to set up a caique parrot habitat [title] Choose a large cage. [step] Although the caique is a medium-sized bird, it needs a great deal of space. Select a cage that can accommodate this energetic parrot. <sep> (A) New cages tend to have more cages that are more hearty and safe, as these should not be bigger than 20 square feet (36 square meters) on all sides. If you're keeping a senior parrot, choose a caique that has built in cage work. (B) When it comes to caique cages, bigger is always better. [substeps] The smallest cage for a single caique should be 24 x 24 x 24 inches (60 x 60 x 60 cm). (C) The standard size for caique quarlings are 4 inches (10 cm) and five feet wide. Add a basking bulb, separate the block of wood with coarse wood shavings and place the bottom on a cooled to room temperature examination table. (D) For a more fluid experience, a small cage that you can comfortably surround your bird in will help to make the experience more comfortable. [substeps] A second enclosure can provide the environment your bird will be inhabiting without having to create a constant environment, changing its structure and its oxygen levels.

Output: B


Input: Consider Input: [header] How to clean a kegerator [title] Clean your kegerator after each keg. [step] Every time you use your kegerator, you should clean it afterwards. This helps remove all beer residue from the line and faucet. <sep> (A) Wipe down your kegerator with a cloth or sponge after each keg brew. [substeps] Make sure you scrub any beards and mats with a soft cloth. (B) Wsers should thoroughly clean the entire tank before storing the kegerator for storage. [substeps] Don't use the motor when cleaning a meter meter and pour your own fluid into the meter. (C) You can loosen the parts that hold up the water line by pulling on a socket wrench or a heavy object. The socket wrench will help you remove the parts of the kegerator you plan to clean. (D) Cleaning after every use helps you avoid messing up other beers. [substeps] If you don't clean between kegs, microbial infections may occur in the kegerator that will alter the beer.


Output: D