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". 

[Q]: [header] How to root the nexus 7 [title] Back up all information on your nexus 7 tablet. [step] All personal data will be erased from your tablet during the rooting process. [substeps] Sync your personal information with google's servers, copy your data over to your computer, or download a third-party cloud storage service app from google play store. <sep> (A) [title] Navigate to the wugfresh website at http: // www.wugfresh.com/nrt /. [title] Select the option to download the nexus root toolkit. (B) Open a folder that houses your cellular data, save the data you want to share and tap backup to backup it to your computer. [title] Follow the on-screen instructions for rooting. (C) [title] Install os x 10.1 on your tablet. [step] After installation, simply tap the " windows " icon on the home screen. (D) If you have a gigabyte device, your tablet will search your phone's applications folder for a root disk that will be used for rooting. [title] Download the latest android root installer.
[A]: A


[Q]: A black object appears and the woman is now placing it onto a long pole, she's back on the ladder and she's using the black object to help her hold up the border wall paper as she applies it all along the wall. when the woman <sep> (A) finishes the wall paper is covered by a blue curtain and she begins to pull the white rod back and forth as she continues to use the soldering iron to create the wall paper. (B) has drawn a border on the wall, she stretches up to get a better hold, three inches above the floor leaving the wall covered in white paper. (C) is done plastering, she takes the phone back and the actual wall paper is now in place and it seems to be the perfect size, exact size and it has sparkles, three big black holes in it and it has the laminate look to make it look very clean. (D) is done the camera pans to show the finished job and the outro appears that includes the website, company name, price and phone number.
[A]: D


[Q]: [header] How to improve mental math skills [title] Visualize the equation in your head. [step] The first step in solving a math problem in your head is to visualize the problem mentally. Imagine the numbers and the equation in your head. <sep> (A) As you solve portions of the problem, visualize the new numbers that you're working with. Repeating numbers mentally or verbally, in a whisper, will also help you to remember more significant numbers in the equation. (B) This way, you'll feel this new image when you see your math papers later in the day. [substeps] You may be more aware of your words and body language when you're visualizing the equation. (C) When you picture the equation, you then have a much better time because you are thinking of the process in your head, rather than the equations. [substeps] For example, imagine that math can be only done in a particular time period. (D) When you think about each answer (number, or word) create a picture about what could happen, and then try to make it into a happy picture. Once you have a picture of each answer in your head, work on how to make it into a happy picture of each part of your brain.
[A]:
A