CCNA: Cisco Certified Network Associate — Question 1258

Which action does the router take as it forwards a packet through the network?

Answer options

• A. The router encapsulates the original packet and then includes a tag that identifies the source router MAC address and transmits it transparently to the destination.
• B. The router encapsulates the source and destination IP addresses with the sending router IP address as the source and the neighbor IP address as the destination.
• C. The router replaces the original source and destination MAC addresses with the sending router MAC address as the source and neighbor MAC address as the destination.
• D. The router replaces the source and destination labels with the sending router interface label as a source and the next hop router label as a destination.

Correct answer: C

Explanation

The correct answer is C because when a router forwards a packet, it modifies the MAC addresses to reflect the current source and destination within the local network segment. Options A and B incorrectly describe the encapsulation process, while option D refers to label switching, which is not the general behavior of a standard router in this context.