Refer to the exhibit.

The correct configuration is option D because Cisco AAA method lists are processed from left to right. The existing configuration uses the default login and exec authorization method lists with only the TACACS+ group. That means if the TACACS+ server is unreachable, authentication and authorization fail unless another method is explicitly listed after the TACACS+ group. Adding local after group tacacs+ creates a fallback sequence: try TACACS+ first; if no TACACS+ response is available, use the local user database. Option C is wrong because it replaces TACACS+ with local authentication only, removing centralized AAA as the preferred method. Option B creates a named method list called FALLBACK, but it does not apply to the default login or exec process shown in the running configuration. Option A is not valid Cisco IOS AAA syntax for this requirement. This is a device-management security question focused on resilient AAA design. References/topics: ENCOR Infrastructure Security, AAA, TACACS+, local fallback, device administration, authorization method lists.