5. CPU scheduler selects the next process for execution. There are several basic scheduling methods, such as first-in-first-out (FIFO), shortest job first (SJF), and round-robin (RR). Regarding to these methods, which of the following comments is INCORRECT? (A) With FIFO, the waiting time of a process may depend on the arriving order of the processes. (B) Starvation won’t occur with FIFO. (C) Theoretically, SJF is an optimal scheduling algorithm in terms of average waiting time. (D) Starvation won’t occur with SJF. (E) RR is a preemptive scheduling algorithm.