Which Coffman condition refers to a resource that cannot be preempted and must be released by the holding process?

• A. Mutual exclusion
• B. Hold-and-wait
• C. No preemption
• D. Circular wait

Answer: (C)

No preemption is the Coffman condition where a resource, once allocated, cannot be forcibly taken away from the holding process; the only way the resource is released is when that process voluntarily releases it. This means the OS cannot interrupt the running process to grab the resource for someone else, so progress can halt if that process ends up waiting for additional resources held by others. For deadlock to occur, this condition can combine with the others—mutual exclusion (resources used by one at a time), hold-and-wait (processes holding resources while waiting for more), and circular wait (a cycle of processes each waiting for a resource held by the next). In contrast, the other conditions describe aspects of resource usage or waiting patterns rather than the fundamental rule that a held resource cannot be preempted.