Which design approach creates the desired result?

A customer called with a requirement that internal clients must be on different subnets depending on the building they are in. All access points are operating in local mode and will not be modified, and this is a single controller solution.

Which design approach creates the desired result?
A . Create AP groups for each desired location, map the correct VLANs to the internal SSID, and add the access points for that location.
B . Create an SSID place it to the desired VLAN under WLANs and configure 802.1x in ISE to assign the correct VLAN based on the SSID from which the client is authenticating
C . Create FlexConnect groups, place the access points in, and set the correct VLAN to SSID mapping based on location.
D . Create mobility anchors for the SSID and on the controller under the internal SSID create a foreign map to the desired VLAN based on location.

Answer: A

Explanation:

https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-vlan/71477-ap-group-vlans-wlc.html