An operating system is (74) .(74)

A． the highest layer of software

B． the lowest layer of software

C． the highest layer of hardware

D． the lowest layer of hardware

[单选题] The （74） scheme in a database system is responsible for the detection of failures and for the restoration of the database to a state that existed before the occurrence of the failure.（74）A． queryB． testC． checkD． recovery

[单选题]A． complete computer system contains(74)。A．arithmetic unit, control unit and memoryB．input/output devices and mainframeC．mainframe. and programs of utilityD．hardware system and software system

[单选题]An operating system is ( ).A.the highest layer of softwareB.the lowest laye

[名词解释] linux operating system

[单选题] An embedded operating system is the（71） program that manages all the other programs in an embedded device after initial load of programs by a(an) （72）. It normally guarantees a certain capability within a specified（73） size and （74） constraint as we

[单选题] As an operating system repeatedly allocates and frees storage space, many physically separated unused areas appear. This phenomenon is called （71） .（71）A． fragmentationB． compactionC． swappingD． paging

[单选题]A．s an operating system repeatedly allocates and frees storage space, many physically separated unused areas appear. This phenomenon is called (71).A．fragmentationB．compactionC．swappingD．paging

[单选题]The operating system provides an easy-to-use (73) to users.(73)A. interfaceB． hardwareC． deviceD． disk

[单选题]A．n embedded operating system is the(71)program that manages all the other programs in an embedded device after initial load of programs by a(an)(72). It normally guarantees a capability within a specified(73)size and(74)constraint as well as with ap

[单选题]Most of the host operating system provides a way for a system administrator to manually configure the IP information needed by a host .Automated configuration methods such as ______, are required to solve the problem.A．IPsecB．DHCPC．PPTPD．SOAP