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: There's an artist painting a square canvas board with several acrylic colors using a flat brush in a studio. she <sep> (A) is painting a christmas tree with a piece of acrylic text. (B) moves the brush across the screen several times. (C) shows how to cut the paint with the flat brush when time stops. (D) begins by painting blue strokes with the flat brush on the canvas surface.
Example Output: D

Example Input: [header] How to avoid the stomach flu [title] Wash your hands often. [step] Wash your hands carefully with soap and water for at least 20 seconds. Always wash your hands after going to the washroom and before and after handling food and eating. <sep> (A) Washing your hands is important, since if the way you handle and eat is bad (germs, bacteria, etc. ), your best chance at preventing the flu is by keeping your hands clean. (B) Don't attempt to dry or clean your hands on something other than a business table. [title] Wear long pants (not utility pants to wear running shoes with). (C) [substeps] It's a good idea to wash your hands between-and as many times as you go to the bathroom. This will help prevent an episode of nausea in the future, as well as allow your body time to shut down its internal defenses to fight off food, germs, and viruses. (D) This will help to prevent the spread of germs. Germs on your hands can get into your eyes, ears, and nose and make you sick.
Example Output: D

Example Input: [header] How to prevent fertilizer runoff [title] Use phosphorus-free fertilizer. [step] Most fertilizer bags will have a ratio of nitrates-phosphorus-potassium printed on the outside of the bag. Look for a number like 32-0-25, where the middle number, denoting phosphorus content, is zero. <sep> (A) A typical fertilizer bag contains 9 nitrates per square foot. [substeps] Phosphate bars can be purchased at gardening and home improvement stores. (B) The different numbers on the bag are also graded according to time of year. [substeps] Phosphate refers to the ratio of nitrogen and nitrogen by the caratomic (or cubic diatomic) process. (C) [substeps] Phosphorous is the largest source of concern when it comes to controlling fertilizer runoff, because it's dangerous to aquatic plants and wildlife. [title] Clean up grass, leaves, and other yard debris. (D) In general, you should use nitrate-free fertilizers. Nitrate levels will fluctuate over time, though nitrates can come in regular amounts, so you should use a balance meter to calculate nitrate levels for all fertilizers.
Example Output:
C