This is a test of commonsense with single/multi-choices. Complete the next sentence:

How to securely wipe an imac or mac os x based system hard drive
Boot an imac or apple-based higher system.
Make sure you've backed up all your necessary data to a thumb or external hard drive.
This data includes important documents, media, itunes files, and bookmarks.

Choose from: (I) You will also need an imac or apple desktop vga if you're using windows os x. once you have this data backed up, use the cds tab at the left to search for it.. (II) Safely remove this thumb or external hard drive so that it is no longer connected to your system. As a precaution, physically detach all connected disks that you do not wish to wipe.. (III) Once you've backed up all your data in your virtualbox, transfer it to a thumb/external hard drive, or use apple's backup app. Once done and connected to your apple computer, follow the on-screen instructions to install virtualbox.. (IV) If you think you will need files or files you don't need, you can " back up " them to home in safe mode. Copy the following into clean and safe mode : Filesystem registry (os x 755)..
The answer is:
(II)