Which of the following is suitable as a description of job scheduling in a computer system?
a) Job scheduling with the FCFS (first-come first-served) method allocates CPU time fairly among jobs, so it is possible to guarantee throughput and response time.
b) When preemption is done using time slices, there are numerous timer interrupts which lower throughput.
c) In a computer system that contains a mixture of interactive and batch processing, improved response performance can be expected when the priority level of interactive jobs is increased.
d) In order to improve throughput, it is more effective to increase the processing priority of jobs that are heavy CPU users than the priority of jobs that are heavy I/O users.