instruction:
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". 
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 make marijuana tea [title] Grind the marijuana buds. [step] Separate out the stems and seeds if necessary, and use a grinder or chop up the buds with a sharp knife until they're finely chopped, but not completely powdered. [title] Mix the buds with butter. <sep> (A) [step] Place them together in a bowl and use a spoon to mix up the buds and butter, making sure each piece is coated with fat. You want the grounds to be completely coated, but not soaked in butter; too much will inhibit the release of thc. (B) [step] Combine two tablespoons (59.6 ml) of butter with 1 teaspoon (4 g) of ground black pepper. Spread this mixture over the marijuana buds, and let it sit for several minutes. (C) [step] Pour the liquid ingredients from the grinder into a blender or food processor, then pulse the contents until well mixed. [title] Punch holes in the buds with a fork. (D) [step] Pour the softened butter into the potting mix. Press the buds down with your finger to blend them together without flaking off.
answer:
A


question:
[header] How to reduce pain caused by a new piercing [title] Ice the piercing. [step] Simply icing the area in question can often soothe some pain associated with piercings. This can be helpful during the first few days, and can also reduce swelling. <sep> (A) You may not know that ice can help reduce swelling-although it can help reduce pain associated with using your piercing when you do wear it. [substeps] Find a bag of ice-wrap the area in a towel and put a small piece of ice wrapped around the area of the piercing. (B) [substeps] Apply ice to the piercing for 5 to 10 minutes at a time to numb the area. If your piercing is still painful after a few minutes, you can always apply a numbing ice pack to the area. (C) Apply something cold, like a bag of frozen peas, or an ice pack to the area during downtime throughout the day. [substeps] Keep in mind, you may want to place a clean, dry rag over the ice pack or cold object to prevent infection. (D) [substeps] The rubbing and squeezing of ice on a new piercing may be enough to numb it. Both ice and regular dental stimulation will also help increase blood flow to the area and reduce pain.
answer:

C