Question Detail User programs interact with I/O devices through ? Operating SystemHardwareBusesProcessor Answer: Option A Ad Similar Questions : 1. __ read the data by reflecting pulses of laser beams on the surface ? Magnetic diskOptical diskFloppy diskROM Answer: Option B 2. What is meaning of PCB ? Process control blockPreempitive control blockProcess close blockProcess carrying block Answer: Option A 3. Which interrupt establishes a priority over the various sources to determine which request should be entertained first ? PollingDaisy chainingPriority interruptAll of above Answer: Option C 4. A number system that uses only two digits, 0 and 1 is known as ? Octal number systemHexadecimal systemBinary systemDecimal system Answer: Option C 5. I/O processor has direct access to ? Main MemorySecondary MemoryFlash MemoryROM Answer: Option A Read more from - Computer System Architecture Questions Answers