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". 

[header] How to make healthy mashed potatoes [title] Wash and cut the potatoes. [step] Wash 1 1/4 pounds (567 g) of your potatoes. You can also use a mix of potatoes and root vegetables for a variety of nutrients. <sep> (A) You can discard the peels, pits, and skins to make only healthy mashed potatoes. [substeps] The mashed potatoes will have a mildly sour texture after this step. (B) Leave the skin on the vegetables and cut them into 1-inch (2.5 cm) pieces. [substeps] Ensure that the pieces are the same size, so they cook evenly. (C) Wash the potatoes out of a colander and rinse them under clean running water. Then rinse each potato under cool, running water for about 5 seconds to remove dirt. (D) Wash the potatoes under hot tap water so they're soft and ready to eat. [substeps] Fresh or frozen mashed potatoes will last 7 to 10 months.
B

A view is seen of the outside of an airport, then the wing of the flying plane. A man is on the plane wearing a mask. several people <sep> (A) are sleeping in the dark quarters. (B) fly by on a road inside the plane. (C) are shown flying the aircraft, while shooting at a large target at one point. (D) speak, then they all fly kites on the plane while people walk by.
A

[header] How to have a great smile [title] Brush your teeth correctly. [step] The single most important thing you can do to keep your teeth healthy is to brush them two to three times a day, using the proper technique. A lot of people fall short in this area, so make sure you understand exactly how you should be brushing your teeth. <sep> (A) Some other tips to keep in mind include chewing gum a few times a day, and being sure you brush well. [title] If you don't currently own a good-quality toothbrush, you might consider buying a decent brush or getting two. (B) [substeps] Each time you brush your teeth, you should brush for approximately two minutes. Try using a timer to help you get the timing right. (C) Keep brushing your teeth and washing your face twice a day. [title] Make sure your teeth are clean and healthy. (D) Brush your teeth at least two times a day, followed by brushing at least twice a day at night and then once every evening. Brushing your teeth will also help to prevent cavities, mouth infections, and gums problems.

B