单项选择题
WhichstatementbestdescribesthebenefitsofCiscoIntegratedServicesRouters？（）
A.Inasingledevice，ISRsprovidethreatdefenseagainstattacksfromhackersandvirusesthatcanoccurinthenetwork.
B.Inasingledevice，ISRsprovidetheframeworktointegrateandextendwiredandwirelessnetworks.
C.InasingledeviceISRsprovideconcurrentsecurity，voice，data，wirelessandapplicationoptimizationservices.
D.Inasingledevice，ISRsprovidethecommonfabric，functionality，andCLIacrossthenetwork.