“Which propagation method is used is dependent upon the platforms in the path. Not all devices are capable of
inline SGT, and some devices support both methods. From an operational perspective, it is best to use inline SGT
because with SXP, you’re building a peering connection that requires maintenance and introduces scaling
limitations. Inline SGT occurs within the data plane so there is no maintenance required.”
It’s A.
SXP is for non-capable sgt inline devices, as WLC.
Sgt Inline capable devices are switches, not wireless controllers.
I would say C – Explanation:
“Which propagation method is used is dependent upon the platforms in the path. Not all devices are capable of
inline SGT, and some devices support both methods. From an operational perspective, it is best to use inline SGT
because with SXP, you’re building a peering connection that requires maintenance and introduces scaling
limitations. Inline SGT occurs within the data plane so there is no maintenance required.”
https://www.cisco.com/c/dam/en/us/solutions/collateral/borderless-networks/trustsec/trustsec_how_to_user_data_center_guide.pdf
For more, see https://www.cisco.com/c/en/us/td/docs/wireless/controller/technotes/8-4/b_wireless_trustsec_deployment_guide.html
Answer A
Cisco WLC added support for SGT classification and SXP transport beginning with the 7.2 release