Final answer:
When a resource is preempted from a process, the process must be rolled back so it can later resume execution. Preemption allows efficient resource sharing in multitasking and real-time systems.
Step-by-step explanation:
If we preempt a resource from a process, the process cannot continue with its normal execution and it must be rolled back. Preemption is a strategy used in multitasking operating systems and real-time systems to ensure that resources are shared among processes in an efficient manner. When a resource is preempted from a process, that process may need to be rolled back to a safe state so that it can be resumed once the resource becomes available again. The process is not necessarily aborted or terminated; it is typically put into a waiting state or queue, ready to continue execution once the resource is returned. Processes may also be designed to handle preemption by saving their state, so they can continue execution without issues once the resource is reclaimed.