单选题：Which of the following descriptions is correct?
Which of the following descriptions is correct? @[C](1)
A. CPU scheduler utilizes an algorithm to select one process from a waiting queue and allocates the processor to it.
B. The wait() and signal() operations can prevent deadlocks.
C. Deadlock prevention can be implemented by ensuring at least one of the four necessary conditions does not happen.
D. When a process tries to enter a critical section, it needs to invoke the unlock() operation.
A.CPU scheduler utilizes an algorithm to select one process from a waiting queue and allocates the processor to it.
B.The wait() and signal() operations can prevent deadlocks.
C.Deadlock prevention can be implemented by ensuring at least one of the four necessary conditions does not happen.
D.When a process tries to enter a critical section, it needs to invoke the unlock() operation.
答案：C
A. CPU scheduler utilizes an algorithm to select one process from a waiting queue and allocates the processor to it.
B. The wait() and signal() operations can prevent deadlocks.
C. Deadlock prevention can be implemented by ensuring at least one of the four necessary conditions does not happen.
D. When a process tries to enter a critical section, it needs to invoke the unlock() operation.
A.CPU scheduler utilizes an algorithm to select one process from a waiting queue and allocates the processor to it.
B.The wait() and signal() operations can prevent deadlocks.
C.Deadlock prevention can be implemented by ensuring at least one of the four necessary conditions does not happen.
D.When a process tries to enter a critical section, it needs to invoke the unlock() operation.
答案：C