Two Cisco 5520 Wireless LAN Controllers are managing all APs throughout the network. The WLCs are in different locations to provide geographical redundancy. A m...

Two Cisco 5520 Wireless LAN Controllers are managing all APs throughout the network. The WLCs are in different locations to provide geographical redundancy.
A mobility group has been configured on both WLCs and has an UP status on both controllers. The APs in location A are statically configured to use controller A as the primary and controller B as the secondary. If the WLC in location A goes offline, the APs successfully join the WLC in location B, but they do not fail over to the primary configured controller. Which configuration task fixes this issue?

A. Enable AP fallback globally on the WLC. B. Change the AP Failover Priority to critical. C. Use DHCP Option 43 and specify WLC in location A as primary. D. Configure the WLC in location A as primary using the CAPWAP AP Controller IP Address command on all the location A APs.