The customer can accesslocal resources(a database server), which meanslocal networking is working.
However, the inability to reach the internet suggests an issue with thedefault gateway. If thedefault gateway is unreachable, packets will not be routed outside the local network.
Breakdown of Options:
* A. Incorrect DNS-DNS issueswould cause problemsresolving domain names, but the user should still be able to access external resources via IP addresses.
* B. Unreachable gateway-#Correct answer.If thedefault gateway is incorrect or unreachable, the devicecannot route traffic to the internet.
* C. Failed root bridge-STP (Spanning Tree Protocol) failurescauseswitching issues, but the user can still access local devices, meaning STP is not the problem.
* D. Poor upstream routing- Wouldaffect the entire network, not just one user.