You will be given a definition of a task first, then some input of the task.
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 screenshare (screencast) on google + hangouts [title] Open up the hangout you'd like to run the screencast in. [title] Hover over the picture in the center of the screen. [step] If you are the only person in the room at the time, you'll see a black screen; hover over the black screen instead. <sep> (A) [substeps] This will make the double screencast. [title] Choose your screencast location and the time it will take to run it. (B) [title] Use the tcp menu to select your desired screencast. [step] You can then scroll through the options, selecting the dialogue boxes, and dragging and releasing the phone. (C) [title] Look and click on the green computer icon. [step] It has an arrow shooting out of it from the left hand toolbar to the page. (D) [title] Draw a spacebar between the two sides of the screen. [step] You can do this either using your pen and place one thumbtack inside of the circle on the right side, or by drawing a curve across the middle of the screen.
Output:
C