Regarding the description of the dual-Border and WAC interconnection design of the campus distributed gateway, which is incorrect?

Regarding the description of the dual-Border and WAC interconnection design of the campus distributed gateway, which is incorrect?
A . In the Overlay interworking solution, it is recommended to run VRRP on Vbdif between the two Borders, and the VRRP virtual address serves as the gateway for wireless users;
B . When wireless centralized forwarding is used, management IP interoperability and service VLAN interoperability are required between WAC and Border, that is, Underlay and Overlay need to be opened;
C . When performing wireless local forwarding, only the management IP needs to be communicated between WAC and Border, that is, Underlay is connected;
D . Supported networking: WAC dual-machine hot backup (VRRP dual-machine hot backup or dual-link hot backup), and dual-Border port sub-type networking, dual-machine VRRP hot backup is recommended; in multi-campus interconnection LAN-WAN integration scenarios, refer to the following topology

Answer: A