Which one of the following is FALSE?

Answer: The statement "Kernel level threads cannot share the code segment" is false.

Explanation:

• "Kernel level threads cannot share the code segment" is false because kernel-level threads of the same process share the process address space, including code and data segments; they have separate registers and stacks but can execute shared code.

• "User level threads are not scheduled by the kernel" is true: a user-level thread library schedules them in user space, while the kernel schedules the process or its kernel thread.

• "When a user level thread is blocked, all other threads of its process are blocked" is generally true for pure user-level threading because the kernel treats the process as a single schedulable entity and blocks it on blocking system calls.

• "Context switching between user level threads is faster than context switching between kernel level threads" is true because user-level switches avoid kernel-mode transitions and associated overhead.