单选题
如下所示是某交换机配置过程中，在配置模式下执行______命令的系统输出信息。
Root Bridge for：VLAN0001
Extended system ID is enabled
PortFast BPDU Guard is disabled
EtherChannel misconfiguration guard is enabled
UplinkFast is disabled
BackBoneFast is disabled
Default pathcost method used is short
Root Bridge for：VLAN0001
Extended system ID is enabled
PortFast BPDU Guard is disabled
EtherChannel misconfiguration guard is enabled
UplinkFast is disabled
BackBoneFast is disabled
Default pathcost method used is short
【正确答案】
D
【答案解析】[解析] “show spanning-tree summary”命令用于显示生成树的总结信息，包括本交换机是哪些VLAN的根网桥、端口快速特性是否启用、处于生成树各个端口状态的端口数量等信息。