单选题：consider the following set of processes, with the length of the

consider the following set of processes, with the length of the CPU-burst time given in milliseconds, a smaller priority number implying a lower priority, the processes arriving in the order P1, P2, P3, P4,P5, all at time 0:
```
Process Burst time Priority
P1 8 3
P2 1 1
P3 2 4
P4 1 3
P5 4 2
```
Which is the most appropriate average waiting time using FCFS scheduling? @[A](1)
A. 8.0 ms
B. 9.0 ms
C. 11.2 ms
D. 18.0 ms





A.8.0 ms
B.9.0 ms
C.11.2 ms
D.18.0 ms


答案：A