What issue might occur if a computer can transfer files locally but cannot connect to the Internet?

• A. The NIC is broken
• B. DNS server is unreachable
• C. The gateway is not routing to a public IP address
• D. The firewall blocks outbound traffic

Answer: (C)

The key idea is how traffic leaves your local network. Local file transfers stay inside the LAN, so they work even if there’s no path to the Internet. The gateway (the router that connects the LAN to outside networks) must route traffic toward a public IP address for Internet access to work. If the gateway isn’t routing to public IPs, outbound packets never reach the Internet, so Internet connectivity fails while LAN access remains intact.

DNS being unreachable would hamper resolving domain names, but you could still reach some sites by their IP address, and with a working LAN you’d often still see local connectivity. A broken NIC would break LAN access entirely, not just Internet access. A firewall blocking outbound traffic could block Internet access but wouldn’t typically explain why LAN file transfers still function. The observed behavior most directly points to the gateway not routing traffic to external networks.