Which three statements are true about load-based Call Admission Control?（）
- Agrants a VoWLAN client-initiated call based on the number of active clients associated to the accesspoint
- Bgrants a VoWLAN client-initiated call based on channel bandwidth capacity
- Cuses the 802.11i specification
- Duses 802.11 action frames
- Erequires a WMM-enabled client