The correct answer is C. Double-sided disk.
A double-sided disk is a disk with usable recording surfaces on each side. This means that it can store twice as much data as a single-sided disk. Double-sided disks were first used in floppy disks, and are now also used in CDs, DVDs, and Blu-ray discs.
A hard disk is a type of storage device that uses magnetic storage to store and retrieve digital information. Hard disks are typically used as the primary storage device in personal computers, but they are also used in servers, workstations, and other devices.
A single-sided disk is a disk with only one usable recording surface. This means that it can store half as much data as a double-sided disk. Single-sided disks were once common, but they are now rarely used.
A high-capacity disk is a disk that can store a large amount of data. High-capacity disks are typically used in devices that require a lot of storage space, such as servers and workstations.
E is not the correct answer because it is not a type of disk.