Which term describes a system designed to ensure no loss of service if a component fails?

The term that best describes a system designed to ensure no loss of service if a component fails is "Fault-Tolerant." Fault tolerance refers to the ability of a system to continue operating properly in the event of the failure of some of its components. This involves implementing various strategies and mechanisms that allow the system to detect failures and, in many cases, automatically switch to a backup component without interrupting service.

For instance, in a fault-tolerant system, if one server goes down, traffic can be rerouted to another server without the end-user experiencing any disruption. This is vital in environments where continuous operation is critical, such as data centers, financial systems, and medical applications, where even brief downtimes can lead to significant consequences.

The other terms described in the options have distinct meanings. While a resilient system is designed to recover from disruptions, it may not necessarily prevent service loss entirely during a component failure. Redundancy refers to duplicating critical components or functions of a system to increase reliability, but it does not explicitly ensure that there will be no loss of service during failures. Backup typically refers to a copy of data or a component that can be used to restore functionality after a failure occurs, rather than maintaining ongoing service without interruption