找考题网-背景图
单项选择题

Which line from the output of the show ip interface com……

Which line from the output of the show ip interface command indicates a layer 1 problem?()

A. Serial0/1 is up, line protocol is down
B. Serial0/1 is down, line protocol is down
C. Serial0/1 is up, line protocol is up
D. Serial0/1 is administratively down, line protocol is down