What differentiates the Cisco OfficeExtend AP mode from the Cisco FlexConnect AP mode?

What differentiates the Cisco OfficeExtend AP mode from the Cisco FlexConnect AP mode?

A. FlexConnect allows a personal SSID to be configured on the AP, and personal SSIDs are not supported with OfficeExtend. B. OfficeExtend does not support DTLS tunneling of traffic to the WLC, and FlexConnect tunnels traffic to the WLC with DTLS. C. FlexConnect must be deployed behind a router that NATs the client traffic, and OfficeExtend uses public IP sources. D. OfficeExtend mode requires indoor APs with internal antennas, and indoor and outdoor APs use FlexConnect mode.