Redundancy is:

A. Scheduling periodic maintenance to improve availability

B. Hiding information to provide confidentiality

C. The provision of surplus service capacity to improve availability

D. None of the above

Option C

Explanation:

Redundancy is the simply the provision of a backup system for an existing system.

Because of safety and protection of important systems and information, redundancy is always a key factor to consider. it is a method of providing a safe, or to prevent a total lose, or shut down of a system, this is achieved by providing "surplus of service capacity to improve availability"as option C explained