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 buy a blackhead remover [title] Learn your options. [step] You should not squeeze or pick at blackhead, as this can lead to infection or scarring. However, you can remove pesky or unsightly blackheads with several different types of products that may not necessarily irritate your skin or require treating it with chemicals. <sep> (A) Learning your different options can help you identify the best product for your specific blackhead removal needs. Products that can remove blackheads include : [substeps] Extractor tools pore strips clay masks topical creams [title] Identify the best remover for your skin type. (B) For example, cleansing a burnt face can peel pores, like blackheads, and subtly remove blackheads. Deep pore pimples, which are a common factor for blackheads, are not tended to dry out. (C) [substeps] Avocado, keratin, and brewer's yeast all work well in reducing the inflammation and scarring of blackheads. [title] Pick a chemical neutralizer for stubborn blackheads. (D) Some of the well known brands that are known for their blackheads include tootane, steam, huawba, and celandine. As noted above, these products are more environmentally friendly than other skincare products, especially for those kids.
Example Output: A

Example Input: [header] How to handle a dog's nightmares [title] Decide whether to wake up your dog. [step] When your dog is having a nightmare, your first instinct may be to wake up your dog. However, this isn't always the best idea. <sep> (A) Waking up your dog would disrupt its sleep cycle, causing it to feel confused and possibly lash out at you. It's often better to let a dog continue sleeping through the nightmare. (B) If your dog's nightmares persist and you aren't willing to take the time to monitor your dog, it might be best to enlist the help of a veterinarian. There are several reasons for this : [substeps] When your dog is having a nightmare, your own judgment is impaired. (C) If your dog is claustrophobic or is fear fearful, you will want to be as calm as possible while your dog is having the nightmare. If the fear is mild to moderate, choosing an alternative position or location may not be a good idea. (D) While nightmares are real, traumatic experiences can also happen. [substeps] Nightmares also occur in dogs that have nightmares caused by trauma.
Example Output: A

Example Input: A boy with earphones is drumming and the stick got stuck in the instrument. The band is playing, while the man is singing, the drummer fell off the his chair. the marching band <sep> (A) unstuck their sticks, and the marching band started their song. (B) started to play and stop. (C) play their drums, then one of the drummers fell on the ground, a person came to help him. (D) is playing important instruments.
Example Output:
C