Which statement is true?（）……

单项选择题When upgrading the IOS image, the network administrator receives the exhibited error message. What could be the cause of this error?（）

A. The new IOS image is too large for the router flash memory.
B. The TFTP server is unreachable from the router.
C. The new IOS image is not correct for this router platform.
D. The IOS image on the TFTP server is corrupt.
E. There is not enough disk space on the TFTP server for the IOS image.

单项选择题This graphic shows the results of an attempt to open a Telnet connection to router ACCESS1 from router Remote27. Which of the following command sequences will correct this problem? （）

A. ACCESS1(config)# line console 0 ACCESS1(config-line)# password cisco
B. Remote27(config)# line console 0 Remote27(config-line)# login Remote27(config-line)# password cisco
C. ACCESS1(config)# line vty 0 4 ACCESS1(config-line)# login ACCESS1(config-line)# password cisco
D. Remote27(config)# line vty 0 4 Remote27(config-line)# login Remote27(config-line)# password cisco
E. ACCESS1(config)# enable password cisco
F. Remote27(config)# enable password cisco

单项选择题A network administrator is troubleshooting the OSPF configuration of routers R1 and R2. The routers cannot establish an adjacency relationship on their common Ethernet link. The graphic shows the output of the show ip ospf interface e0 command for routers R1 and R2. Based on the information in the graphic, what is the cause of this problem?（）

A. The OSPF area is not configured properly.
B. The priority on R1 should be set higher.
C. The cost on R1 should be set higher.
D. The hello and dead timers are not configured properly.
E. A backup designated router needs to be added to the network.
F. The OSPF process ID numbers must match.

单项选择题While troubleshooting a connectivity issue from a PC you obtain the following information: Local PC IP address: 10.0.0.35 24 Default Gateway: 10.0.0.1 Remote Sever: 10.5.75.250 24 You then conduct the following tests from the local PC: Ping 127.0.0.1 – Successful Ping 10.0.0.35 – Successful Ping 10.0.0.1 – Unsuccessful Ping 10.5.75.250 – Unsuccessful What is the underlying cause of this problem?（）

A. A remote physical layer problem exists.
B. The host NIC is not functioning.
C. TCP/IP has not been correctly installed on the host.
D. A local physical layer problem exists.

单项选择题As a CCNA candidate, you must have a firm understanding of the IPv6 address structure. Refer to IPv6 address, could you tell me how many bits are included in each filed?（）

A. 24
B. 4
C. 3
D. 16