While troubleshooting a connectivity problem, a network administrator notices that a port status LED on a Cisco Catalyst series switch is alternating green and amber． Which condition could this indicate?

A、 The port is experiencing errors．
B、 The port is administratively disabled．
C、 The port is blocked by spanning tree．
D、 The port has an active link with normal traffic activity．

【正确答案】 A

【答案解析】CISCO交换机的端口状态指示灯是闪烁的绿色和浅黄色，表示端口有操作的问题——也许是过量的错误或连接的问题。