Which layer handles the addition of IP addresses to each packet and governs routing across networks toward the destination server?

• A. Layer 3 Network
• B. Layer 2 Data Link
• C. Layer 4 Transport
• D. Layer 1 Physical

Answer: (A)

This question is about where IP addressing and inter-network routing are performed. The Network layer is responsible for logical addressing with IP addresses and for routing packets across multiple networks toward the destination server. It adds the IP header containing the source and destination IPs and relies on routers to forward packets along the best path using routing tables and protocols. The Data Link layer handles local delivery within a single network using MAC addresses, the Transport layer manages end-to-end communication and ports, and the Physical layer covers the actual transmission of raw bits. So, the Network layer is where IP addresses are added to packets and routing across networks is governed.