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".
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Question: [header] How to use psychology to close more sales [title] Give something for free. [step] The principle of reciprocation is a psychological phenomenon described by dr. robert cialdini, an expert in persuasion. According to this theory, it is part of human nature to feel obligated to repay debts of all kinds, big and small. <sep> (A) To begin this process, ask yourself if you really are willing to sell something for free. If you are willing to throw in the money, then you are probably willing to take credit. (B) You can't force anything on someone else. [substeps] If you " feel " obligation to a friend or loved one, give them something to ask you " if i use this method, what will happen? " [title] Assemble your argument. (C) If someone receives something free, they will feel a psychological urge to purchase a product to pay you back for your kindness. [substeps] Offer a free trial period, a sample, or even a pleasant experience. (D) To do this you must pay for or at least accept the full offer. After that you must devise a plan of compensation.

Answer: C

Question: [header] How to band a goat [title] Purchase an elastrator from a farm and ranch supply store. [step] It is a metal tool that is used to secure the rubber band around the scrotum. [title] Buy castration bands. <sep> (A) [step] They can be purchased from your local farm supply store or from a municipal livestock supply store. [title] Buy a leather or gauze band. (B) [step] Don't use household office supplies for banding. The bands should be thick enough and tight enough to lead to castration within a few weeks. (C) [step] These are simple, metal with metal screws, two prongs, and a ribbon loop on either end. [title] Cut a small hole in each long length of the band. (D) [step] It is a device that attaches the separate rubber bands, wires, tubing and pieces of cork/plastic. It is available at local farm supply stores, ranch supply stores and hardware stores.

Answer: B

Question: A person gather mops and cleaning materials on a hard floor. the person <sep> (A) lifts the mops and down the floor, then part the carpet material. (B) cleans the hard floor using a dust mop. (C) holds a stuffed animal in his hand while moving. (D) cleans art pieces on a dusty floor.

Answer:
B