An engineer in a branch office that does not have a wired backhaul must ensure...

Flex+Bridge mode is a specialized AP operating mode that combines two distinct Cisco wireless capabilities: FlexConnect (for local switching of client data traffic and central authentication via the WLC) and Bridge/Mesh mode (enabling wireless backhaul when no wired Ethernet uplink is available). In a branch environment without wired backhaul, a standard FlexConnect AP (Option D) cannot operate because FlexConnect still requires an Ethernet connection for its control plane. Bridge mode alone provides mesh backhaul but does not support the local switching with central authentication model required here. MAP (Option A) is a Mesh Access Point role for wireless backhaul, and RAP (Option C) is a Root Access Point with a wired connection — neither meets the no-wired-backhaul requirement with local switching. Flex+Bridge uniquely satisfies both requirements: the Flex component allows locally switched VLANs to be bridged directly to the access layer without traversing the WAN, while the Bridge component enables the AP to use a wireless mesh link for its backhaul uplink. Central authentication is maintained via the CAPWAP control tunnel over the mesh link. Reference: WLSD Study Guide — FlexConnect Design, Mesh Networking, Flex+Bridge Mode Configuration and Use Cases.