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 Q]: [header] How to lance and drain a blister [title] Assess the blister before choosing to drain it. [step] Not every blister needs to be lanced. In fact, some experts recommend that you should only drain blisters that are exceedingly painful, in weight-bearing or high-contact areas, or larger than 0.8 inches (2 centimeters) in diameter. <sep> (A) [substeps] If the blister is intact and manageable, try to keep it intact. Apply a piece of moleskin, adhesive felt, or tape. (B) In these instances, you need to check the blister to determine if it needs a leak-proof drain. [substeps] See the " how to drain a blister " section of this article for instructions. (C) [title] Make a decision whether or not to drain the blister. [step] If the blister is very painful, medical sterilization is an option. (D) [substeps] There is no one right way to do this, so you have to be sure that you have the right technique. It is not as easy to clean a blister as to rinse with water and applying a sterile dressing.
[EX A]: A

[EX Q]: [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 ¼ 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 A]: B

[EX Q]: [header] How to repeat songs on ios 10 [title] Tap your home button. [step] If you have a passcode enabled, this will prompt you to enter your passcode; otherwise, this will take you to the home screen. [title] Tap the " music " app. <sep> (A) [step] This will open your music app to the last song, playlist, album, or similar item that you had open. [title] Tap the " library " tab in the lower left corner of your screen. (B) [step] This icon is usually located in the upper left-hand corner of your screen. [title] Scroll to the playlist you want to add your song to. (C) [step] This will download the music playlist app from the app screen. [substeps] If your device is locked, you may not be able to find the music playlist app. (D) [step] This will bring up your home screen, and open the sounds list. [title] Tap " sound, " then tap " find a song or track.
[EX A]:
A