Which spanning-tree command would cause a PortFast-enabled interface to lose its PortFast-operational status and disable BPDU filtering if it receives BPDUs？（）

单项选择题Whichofthefollowingconditionsguaranteesthatabroadcaststormcannotoccur？（）

A.a native VLAN mismatch on either side of an 802.1Q link
B.BPDU filter configured on a link to another switch
C.Spanning Tree Protocol enabled on both Layer 2 and multilayer switches
D.PortFast enabled on all access and trunk ports

单项选择题WhichstatementistrueregardingthePortAggregationProtocol？（）

A.Configuration changes made on the port-channel interface apply to all physical ports assigned to the portchannel interface.
B.Configuration changes made on a physical port that is a member of a port-channel interface apply to the port-channel interface.
C.Configuration changes are not permitted with Port Aggregation Protocol； instead， the standardized Link Aggregation Control Protocol should be used if configuration changes are required.
D.The physical port must first be disassociated from the port-channel interface before any configuration changes can be made.

单项选择题WhichcommandalonewilldisabletrunkingonaLayer2switchport？（）

A.no switchport trunk native vlan vlan-id
B.switchport nonegotiate
C.no switchport mode dynamic desirable
D.switchport mode access

单项选择题WhichconfigurationoptionwillcausethelinkbetweentwoCisco3600SeriesMultiservicePlatformstobecomeafunctionaltrunk？（）

A.switchport dynamic auto switchport dynamic auto
B.switchport access vlan 10 switchport mode dynamic desireable
C.switchport mode trunk switchport nonegotiate
D.Leave both ports with the default trunk settings

单项选择题Whatistheeffectofapplyingtheswitchporttrunkencapsulationdot1qcommandtoaportonaCiscoCatalystswitch？（）

A.By default， native VLAN packets going out this port will be tagged.
B.Without an encapsulation command， 802.1Q will be the default encapsulation if DTP fails to negotiate a trunking protocol.
C.The interface will support the reception of tagged and untagged traffic.
D.If the device connected to this port is not 802.1Q-enabled， it will not be able to handle 802.1Q packets.