What feature(s) are most likely to be supported by 802.11 enterprise-class WLAN controllers?

What feature(s) are most likely to be supported by 802.11 enterprise-class WLAN controllers?
(Choose 4)

A.
Link aggregation / port trunking

B.
802.1p and DSCP QoS

C.
BGP and Frame Relay

D.
Captive web portals

E.
IGMP snooping