[单选题]

C．atalyst 3500(Cisco．[OS系统)中配置PortFast生成树可选功能的命令格式是——。
A．set spanning—tree portfast<mod／port>enable
B．set spanning-tree portfast<mod／port>enable
C．spanning—tree portfast default
D．set spanning—tree portfast<mod／port>default

C．atalyst 3500(Cisco．[OS系统)中配置PortFast生成树可选功能的命令格式是——。A．set spanning—tree portfast<mod／port>enableB．set spanning-tree portfast<mod／port>enableC．spanning—tree portfast defaultD．set spanning—tree portfast<mod／port>default