MIMD systems can be classified into (1) -oriented systems, high-availability systems and response-oriented systems. The goal of (1) -oriented multiprocessing is to obtain high
(1) (2) minimal computing cost. The techniques employed by multiprocessor operating systems to achieve this goal take advantage of an inherent processing versus input/output balance in the workload to produce (3) and (4) loading of system (5)

A．though

B．through

C．throughout

D．throughput