What does redundancy refer to in improving system reliability?

Redundancy in the context of improving system reliability refers to the practice of utilizing backups or alternative components. This involves incorporating additional elements into a system so that if one component fails, others can take over the function, thereby ensuring the system remains operational. For example, in a network, having multiple servers or data pathways enhances reliability because if one server goes down, others can continue to serve users without significant disruption.

This approach is crucial in critical systems, such as transportation, healthcare, and information technology, where failure can lead to serious consequences or downtime. By having redundant systems in place, organizations can minimize the risk of failure and maintain a higher level of service without interruption.

The other choices, while potentially relevant in certain contexts, do not accurately capture the essence of redundancy aimed at enhancing reliability.