Read-only memory, or ROM, stores instructions for critical system activities, especially the firmware used during startup. In Information Technology fundamentals, ROM contains non-volatile instructions that remain available even when the computer is powered off. These instructions typically include the system firmware responsible for initializing hardware, performing basic checks, and starting the boot process that loads the operating system. Because ROM is designed to retain its contents without power, it is appropriate for storing essential routines that the computer must access immediately when it turns on. RAM is volatile and loses contents when power is removed, so it cannot reliably store permanent startup instructions. The CPU executes instructions but does not store firmware permanently. The GPU is a specialized processor for graphics and parallel workloads and is not responsible for storing core boot instructions. Although modern systems often use flash-based firmware rather than older fixed ROM chips, this is still categorized as ROM or ROM-like non-volatile firmware storage in many IT documents. Therefore, the correct component is ROM.