What is the primary role of GRUB in a Linux system?

The primary role of GRUB, which stands for Grand Unified Bootloader, in a Linux system is to determine and manage the boot process of the operating system. When a computer is powered on, GRUB is the first software that runs, and it presents a menu that allows users to select which operating system or kernel they want to boot into. This is particularly essential in systems with multiple operating systems installed, as it provides a simple interface for selecting the desired option. GRUB's role is crucial because it not only initializes the boot sequence but also loads the selected operating system into memory, enabling the system to start functioning.

In contrast, managing file permissions, configuring network settings, and monitoring system performance are unrelated functions that are handled by other components of the Linux system. File permissions are managed by the Linux kernel and file system, network configurations are typically handled through network management tools and files, and performance monitoring is achieved using specialized utilities designed to track and analyze system resources. Thus, the correct answer highlights the specific function of GRUB in the overall operation of a Linux environment.