单项选择题 AnOSPFnon-backboneareaallowsexternalroutestobefloodedwithinthearea.Theseexternalroutesarepropagatedintootherareas.However，externalroutesfromotherareasarenotallowedtoenterthisarea.WhichtypeofSPFareadoesthisdescribe？（）A.stubareaB.transitareaC.borderareaD.not-so-stubbyarea

单项选择题 WhichJUNOSsoftwareoperational－modecommanddisplaysthestatusofaDraft－MartiniVPN？（）

单项选择题 AnIS－ISrouterisadjacenttoandpassingtrafficwithaneighbor.Youperformashowis interfacedetailcommandandnoticethatforsomeinterfacesyouhaveacircuittypeof3.WhichIS－ISlevel（s）isenabledontheseinterfaces？（）

单项选择题 WhichactionoccurswhentheBGProute20.1.0.0/16isevaluatedbythepolicyexpression？（）[editpolicy-options]policy-statementmy-filter{term-first{from{route-filter192.168.0.0/16orlongeraccept；route-filter192.168.1.0/24exactaccept；route-filter192.168.2.0/24exact；}then{metric10；accept；}termsecond{then{metric20；accept；}}policy-statementmain{termchange-attributesfrom{policymy-filter；}thenaccept；}termdefault{thenreject；}}[editprotocols]bgp{exportmain；}A.TherouteisnotadvertisedintoBGPB.TherouteisadvertisedintoBGPwithmetric10.C.TherouteisadvertisedintoBGPwithmetric20.D.TherouteisadvertisedintoBGPwithdefaultmetric.

单项选择题 GiventhetwoASpathregularexpressions："65000＋（65001|65002）""65000＋（65001|65002）{0，}"WhichASpathmatchesbothexpressions？（）