单选题：In a dual-mode (kernel mode and user mode) system, which of the

In a dual-mode (kernel mode and user mode) system, which of the following components are not necessary? @[D](1)
A. A bit in the hardware to indicate the current mode.
B. Privileged instructions.
C. Operating system running in the kernel mode.
D. Some user programs in the kernel mode.





A.A bit in the hardware to indicate the current mode.
B.Privileged instructions.
C.Operating system running in the kernel mode.
D.Some user programs in the kernel mode.


答案：D