单项选择题
A. Improves convergence of the multicast network due to enhanced RPF checks
B. Simplifies the number of control plane protocols over other RP redundancy methods
C. Eliminates the use of Protocol Independent Multicast （PIM） in the topology
D. Increases the administrative distances in Multicast Source Discovery Protocol （MSDP） configuration
单项选择题 2012 Feb 23 23：00：08.676710 pim： [16132] （default-base） Received unauthenticated hello- message from 10.1.1.2 on Ethernet1/18， message discarded 2012 Feb 23 23：00：12.528763 pim： [16132] （default-base） Send Hello with AH on Ethernet1/18 from 10.1.1.1， holdtimE. 105 secs，dr-priority：1 You are troubleshooting a PIM neighbor adjacency that is not coming up. You issued the command show ip pim neighbor e1/18 and confirmed there is no PIM neighbor on the interface. What is the problem based on the debug output？（）
单项选择题 OntheCiscoNexus7000SeriesSwitch，ControlPlanePolicingisenforcedonwhichcomponent？（）
单项选择题 OnCiscoNexus5000SeriesSwitches，wherearethevirtualoutputqueuesimplemented，andwhatisthemainpurposeofvirtualoutputqueues？（）