ICANN or Internet Corporation for Assigned Names and Numbers is the agency that coordinate the Internet's IP addressing and NS system. It is basically a non profit organization and it is solely responsible for this job. The main responsibility of this organization is preserving the internet's operational stability.
If you plan to use it as a back-up then you'd most likely want to keep it external, and connect it via USB. If you're looking to format it, you can use OSX's Disk Utility, or the OS equivalent for Windows or Linux.
The correct answer is C, as hot keys do perform functions a computer mouse could.
