Which term describes the ability of a system to expand to handle more users without malfunctioning?

The term that best describes the ability of a system to expand to handle more users without malfunctioning is scalability. Scalability refers to a system's capacity to increase its resources and performance as the demand grows. This can involve adding more servers, enhancing processing power, or optimizing resources to ensure that the system continues to function efficiently and effectively under higher loads.

In the context of technology and software architecture, scalability is critical for maintaining performance levels during peak usage times and ensuring that users have a seamless experience regardless of how many are accessing the system simultaneously. It encompasses both vertical scaling, where resources are added to a single node, and horizontal scaling, where more nodes are added to distribute the load.

The other terms, while related to system performance and adaptability, do not specifically capture this essential feature of being able to handle increasing demands efficiently without failure. For instance, modifiability pertains to how easily a system can be changed or updated, expandability suggests adding components or features, and disintermediation refers to eliminating intermediaries in a process. Each of these concepts plays a role in the broader scope of system design, but scalability precisely addresses the need for performance management related to growth in user numbers.