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 reinstall and obtain all of the drivers on a dell studio xps [title] Locate your windows 7 install disc. [title] Insert it into your drive. [title] Turn your machine off. <sep> (A) [title] Check the cd case to see if you have any discs that you need. [step] If they are missing you can use the " remove disc " installer. (B) [title] Reboot your machine and immediately start tapping f2 which will take you to the bios setting screen. [title] Use the arrow keys to select the boot tab and press enter. (C) [step] Do this 1 right on the computer from left to turn it off. [title] Go to programs manager and start programs' " disk cleanup " wizard. (D) [title] Take your hardware manager from your pc and open usb-and usb cable from your hardware manager. [title] Connect the power strip to the support tube and then right-click on the cable.

Answer: B

Question: [header] How to exercise to prevent blood clots [title] Get up and move around. [step] Whether you're traveling by train, plane, or automobile, long-distance travel involves a lot of sitting. When you sit, you decrease circulation in your legs-especially if you sit with your legs crossed or with one foot under you. <sep> (A) If you are on a train or coach, the seat underneath you always feels flat, as if you are sitting. While there are good ways to stretch out your legs, there is not a lot a group of people can do. (B) This will help promote blood circulation to your feet. It will also keep you from rubbing your legs in an annoying manner-you can't promote blood flow when you're sitting on one leg. (C) [substeps] You can exercise while you drive or driving, although getting up and down on the exercise train can significantly improve circulation. You can also listen to music while you exercise, which will also help to prevent blood clots. (D) [substeps] If you're on a plane, try to get an aisle seat so you can get up and move around more easily. Ideally, you want to get up and stretch your legs or walk up and down the aisle once every hour or so.

Answer: D

Question: [header] How to prepare mashed potatoes [title] Peel the potatoes. [step] After you wash the potatoes thoroughly under cool water, use a sharp knife or a potato peeler to peel off the skin. You can also keep the skin on yukon gold or red skin potatoes, if you like, but baking potatoes should be peeled. <sep> (A) [substeps] Peel the potatoes if you decide to peel them. Puree the potatoes instead of peeling them. (B) [title] Heat oil in a large skillet over medium heat. [step] Turn off the heat and add the oil to a large skillet. (C) [title] Boil the potatoes in a large pot of water. [step] First, boil the water by itself, adding a pinch of salt. (D) [substeps] Peeled potatoes, then with a fork, mash them. Pureeing for several days will ensure that it doesn't spoil, and more importantly, it's an easy and healthy way to roast the potatoes.

Answer:
C