You are troubleshooting an issue which is causing full-sized packets entering the MPLS cloud be dropped. You have discovered that one of the switches in the MPLS core is not a Cisco switch, but otherwise the MPLS MTU size is set to 1508 bytes on the routers.
Based on this information, which of these may be the reason the packets are being dropped?（）

单项选择题Assuming that an IP packet is sent from a source address in VLAN1 to a destination address in VLAN2 through a layer-3 switch, which part of the packet will be changed?（）

A. Layer 2 TTL
B. Layer 3 TTL
C. Layer 3 source address
D. Layer 3 destination address

单项选择题On a Cisco Catalyst 4500 Series, the fail LED is lit for one if its two power supplies. Which command would you use to check on this problem ?（）

A. Show module
B. Show errdisable detect
C. Show environment
D. Show diagnostic content

单项选择题A Catalyst switch has just been installed and configured, and is not working as expected. You have decided to capture multiple show command outputs to study. Which one command could you use that includes the output of many other show commands, such as show version and show running-config?（）

A. show configuration
B. show memory
C. show stacks
D. show tech-support

单项选择题As an experienced Network Engineer, you are required to implement the security architecture assessment. Which of the following statement describes the most important reason for that?（）

A. Create a design specification document.
B. Integrate routing and switching components.
C. Document power and UPS availability
D. Document the customer's current and future technology projects.

单项选择题The Cisco Enterprise Campus Architecture increases the effectiveness of networked applications and services on campus, enabling enterprises to grow their business and stay ahead. What is the outcome of designing all its components with taking interoperability into consideration?（）

A. improved connectivity options
B. strengthened security
C. high availability
D. continuity of service