Which of the following statements are TRUE about Privileged Instructions? (A)…

Correct answer: The statements that privileged instructions can only be executed by the operating system kernel and that they are designed to perform operations that directly affect hardware or system state are true. The other statements are false.

• Statement about kernel-only execution: Privileged instructions require supervisor (kernel) mode and cannot be executed directly by user applications. This restriction is enforced by the CPU to maintain isolation and security.

• Statement about affecting hardware or system state: True. Privileged instructions perform sensitive operations such as I/O control, changing memory management settings, and other actions that affect global system state.

• Statement about user applications executing privileged instructions: False. User programs cannot execute privileged instructions even if "permissions" were conceptually granted; they must use system calls or other controlled kernel interfaces so the kernel executes the privileged operations on their behalf.

• Statement about privileged instructions executing in user mode: False. Executing privileged instructions in user mode would bypass hardware-enforced protection and compromise safety and security; therefore they run in kernel (supervisor) mode.

Key takeaway: Privileged instructions are reserved for kernel execution and are used for operations that can affect hardware or global system state. User-level code uses system calls to request such operations from the kernel.