What is the significance of time slices in process scheduling?

Time slices are crucial in process scheduling because they establish a mechanism for distributing CPU time among multiple processes in a fair manner. By dividing the CPU's available time into small, manageable intervals—called time slices—this approach ensures that no single process monopolizes the processor. As each process is allotted a time slice during which it can execute, multiple processes can make progress concurrently in a time-sharing system.

This scheduling strategy is particularly effective in multitasking environments, where numerous applications or processes are competing for CPU resources. By providing each process with a fair share of CPU time, time slices help to optimize responsiveness and performance, enabling the system to handle user interactions and background tasks more fluently.

In contrast, the other options don't accurately reflect the role of time slices in process scheduling. For instance, while time slices may limit how long a process runs at one time, they do not prevent multiple processes from running; instead, they facilitate this by ensuring fairness and efficiency in CPU usage. Furthermore, time slices are explicitly designed to avoid indefinite execution of processes and do not inherently limit I/O operations, as I/O scheduling functions involve different mechanisms.