Given the task definition and input, reply with output. 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 align tracks in audacity [title] Open the audacity program. [step] You should see the main screen, with colored controls at the top and gray space for available tracks underneath. [title] Record your original track. <sep> (A) [step] Delete the itunes tracks and save the originals in a folder for the future. Double-click on the tracks that are in your pre-installed program. (B) [step] From the menu on the bottom panel, select " view all tracks " from the pop-up menu. Set the track (s) you wish to record as your mobile app. (C) [step] You can import from recorded tracks, import from a set, or purchase. [substeps] Select the track you want to record and click the plus sign to find the track. (D) [step] You will see the track populate with lines that represent sound modulation, directly under the controls. [substeps] Use your initial track as a marker for rhythm and timing.

D