单选题：Consider the following three threads in a concurrent program tha

Consider the following three threads in a concurrent program that uses semaphores Sem1, Sem2, and Sem3.What are the initial values that can be given to the semaphores so that the threads cooperate to print a string that begins with 162162162162162? @[D](1)
```
Thread 1
L1: sema_down(Sem1);
print(“6");
sema_up(Sem2);
goto L1;

Thread 2
L2: sema_down(Sem2);
print(“2");
sema_up(Sem3);
goto L2;

Thread 3
L3: sema_down(Sem3);
print(“1");
sema_up(Sem1);
goto L3;


```

A. sem1=0, sem2=0, sem3=0
B. sem1=1, sem2=1, sem3=1
C. sem1=0, sem2=1, sem3=0
D. sem1=0, sem2=0, sem3=1




A.sem1=0, sem2=0, sem3=0
B.sem1=1, sem2=1, sem3=1
C.sem1=0, sem2=1, sem3=0
D.sem1=0, sem2=0, sem3=1


答案：D