Routing involves two basic activities: Path determination and packet switching.

• A. Path determination and packet switching
• B. Pathfinding and data encapsulation
• C. Addressing and forwarding
• D. Routing table maintenance

Answer: (A)

Routing is about two main actions: deciding the best path to reach a destination and then moving each packet along that path. The first step, path determination, uses the network’s topology, metrics (like cost, delay, or bandwidth), and routing algorithms to choose the optimal route. The second step, packet switching (forwarding), takes each incoming packet and sends it toward the next hop along the chosen path, using the router’s forwarding/routing table to decide where to send it next. Together, these two activities describe how routing works: pick the route, then push packets along it.

Other options don’t fit as cleanly. Data encapsulation is about adding protocol headers and trailers, a layer-related process rather than a routing decision and forward operation. Addressing and forwarding splits the task into identifying endpoints and then moving data, but addressing isn’t one of the two core routing activities. Routing table maintenance is essential for keeping routes up to date, but it’s a support function rather than the primary pair of activities that define routing.