John is discussing security with Jane. Jane had mentioned to John earlier that she suspects an LKM has been installed on her server. She believes this is the reason that the server has been acting erratically lately. LKM stands for Loadable Kernel Module.

What does this mean in the context of Linux Security?

A.
Loadable Kernel Modules are a mechanism for adding functionality to a file system without requiring a kernel recompilation.

B.
Loadable Kernel Modules are a mechanism for adding functionality to an operating-system kernel after it has been recompiled and the system rebooted.

C.
Loadable Kernel Modules are a mechanism for adding auditing to an operating-system kernel without requiring a kernel recompilation.

D.
Loadable Kernel Modules are a mechanism for adding functionality to an operating-system kernel without requiring a kernel recompilation.

Explanation:
Loadable Kernel Modules, or LKM, are object files that contain code to extend the running kernel, or so-called base kernel, without the need of a kernel recompilation. Operating systems other than Linux, such as BSD systems, also provide support for LKM’s. However, the Linux kernel generally makes far greater and more versatile use of LKM’s than other systems. LKM’s are typically used to add support for new hardware, filesystems or for adding system calls. When the functionality provided by an LKM is no longer required, it can be unloaded, freeing memory.