Which configuration change 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 configuration change creates the desired result?
A. Set the SSID to the desired VLAN under WLANs, configure 802.1x ACS to assign the correct VLAN based on the SSID the client is authenticating from.
B. Create AP groups for each desired location, map the correct VLANs to the internal SSID, and add the access point for that location.
C. Configure the access point in the FlexConnect mode 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.