Final answer:
The kernel is resident software that remains in memory to manage system resources, allocate memory, and handle I/O requests for efficient computer operation.
Step-by-step explanation:
The kernel is resident software, which means it remains in memory while the computer is running. The kernel is the most crucial part of the operating system as it manages system resources, allocates memory, handles input and output requests from software, and manages hardware so different software programs can use it without conflicting with each other. Since the kernel performs essential functions for the computer's operation, it must remain in memory so actions can be executed efficiently and quickly.