Refer to the exhibit.

10.8.138.0/24. The answer follows from standard Cisco behavior and the operational clue in the scenario. Cisco CCNA 200-301 v1.1 includes this under Network Fundamentals, where the expected skill is to identify the feature that actually creates the observed behavior or meets the configuration goal. The wording usually contains the decisive clue: a prefix length, a VLAN role, a protocol version, a wireless security standard, or a management-plane function. The other choices describe related terms, but they do not satisfy the requirement stated in the prompt. In an operational network, choosing the wrong option would typically cause failed connectivity, insecure management, poor wireless behavior, or incorrect forwarding. The selected answer matches the Cisco configuration model and is retained as the verified answer.