Which one of the following is NOT shared by the threads of the same process?

Answer: Stack is NOT shared by threads of the same process.

• Stack — Each thread has its own call stack and CPU context (registers). The stack holds local variables and return addresses and must be separate to prevent interference between threads.

• Address space — All threads share the same virtual address space, allowing shared access to globals and the heap.

• File descriptor table — Open file descriptors are process-wide and visible to every thread in the process.

• Message queue — IPC objects like message queues are accessible to threads in the same process; the queue is managed at the process/kernel level and can be used by any thread.

Therefore, the stack is the correct answer because it is the per-thread resource, while the others are shared by threads of the same process.