What part of the operating system loads first and remains in the main memory?

The bootloader is the part of the operating system that loads first during the system startup. It initializes the hardware and loads the kernel into the main memory, which remains there to manage system resources and execute processes. The kernel serves as the core component of the operating system, facilitating communication between hardware and software. Once loaded, the bootloader typically relinquishes control to the kernel, which takes over the system's operations.