Which of the following is the MOST common method of memory protection?

Compartmentalization is a broader security principle of isolating systems or data by sensitivity level, not a specific memory protection mechanism used by hardware or operating systems.

Segmentation divides memory into distinct segments (code, data, stack) assigned to processes, with hardware-enforced boundaries that prevent one process from accessing another's memory space. This is implemented at the CPU level (e.g., x86 segment registers and descriptor tables) and is the most common and fundamental memory protection mechanism used in modern computing. It directly addresses confidentiality and integrity of data in memory by enforcing access controls at the hardware level.

Error correction (ECC) detects and corrects memory bit errors caused by hardware faults or radiation, addressing data integrity at a hardware reliability level rather than protecting memory from unauthorized process access.

VLAN tagging (IEEE 802.1Q) is a network-layer technique used to logically segment network traffic on switches and has no relevance to memory protection within a computing system.