单项选择题 You work as a network engineer at TestKing.com. TestKing users have noticed extremely slow network performance, intermittent connectivity, and connection loss. After entering the show interfaces command, you notice that the Ethernet interface is configured as 100 Mbps full-duplex and that there is evidence of late collisions. What could be the cause of this problem?（）

多项选择题 While troubleshooting connectivity issues, you log into a remote router. From there,you wish to see the layer 1 and layer 2 status of the interface. Which of the following IOS commands would you issue to check the current IP addressing, as well as theyer 1 and layer 2 status of an interface?（）

单项选择题 While troubleshooting a connectivity issue from a PC you obtain the following information: Local PC IP address: 190.0.3.35/24 Default Gateway: 190.0.3.1 Remote Server: 190.0.5.250/24 You then conduct the following tests from the local PC: Ping 127.0.0.1 - Unsuccessful Ping 190.0.3.35 - Successful Ping 190.0.3.1 - Unsuccessful Ping 190.0.5.250 - Unsuccessful What is the underlying cause of this problem?（）