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 make scented rocks [title] Purchase supplies from a local department store or craft store. [step] You will need plain flour, salt, food coloring and essential oils. Essential oils are oils that have been extracted from various plants. <sep> (A) You do not need to use all different oils, but big quantities will work. [substeps] Choose oils that you associate with fresh fruits and vegetables and herbs. (B) It can be easily purchased at craft supply stores or you may be able to find them online. Get an essential oil primer, then make sure your acrylic rock is thoroughly coated. (C) You can also purchase essential oils from craft stores, or you can order a variety of essential oils online. [title] Mix together 1/2 cup (118 ml) of plain flour and 1/2 cup (118 ml) of salt in a mixing bowl. (D) You will need and obtain the following materials : [substeps] A 40 oz mixing bowl large enough to fit the stones. If you do not have these materials to gather, a mixing machine at an arts and crafts store can be more economical than a large ceramic mixing bowl, which will require little or no space.
Example Output: C

Example Input: [header] How to make black coffee [title] Purchase freshly roasted, whole bean coffee. [step] If you can't purchase it directly from the roaster within a week or so of it being roasted, opt for a vacuum-sealed bag from a reputable national coffee-bean roaster. [title] Purchase your own coffee grinder, or grind it in the store. <sep> (A) [step] If possible, choose a burr grinder in place of a normal blade grinder. For best results, grind the coffee fresh right before brewing each day. (B) [step] Grind coffee beans in the near-black zone of a coffee grinder. You can use either a regular-size grinder or a pre-grind grinder to grind your coffee. (C) [step] Modern coffee grinders have drawbacks, as they require higher temperatures to make purified coffee. Where possible, purchase one that comes pre-boil. (D) [step] Print it onto a piece of paper, remove the lid from the coffee grinder, and grind the coffee beans in the machine's center. [title] Unplug the coffee grinder and plug it into the wall outlet.
Example Output: A

Example Input: One of the men is using a controller to make the arm pick up a bottle. The arm brings the bottle to the man's face, so he can take a drink. then the robot <sep> (A) arrives and grabs the bottle and the person makes the arm grab. (B) removes the bottle and drinks. (C) has to take it away again. (D) returns the bottle to the table.
Example Output:
D