Which explanation describes a wireless client IGMP multicast join request using a Cisco Unified Wireless Network v5.2 architecture of AP to WLAN controller?（）

A. passed by the AP to its connected switch and then forwarded directly to the connected router，which creates an MGID table entry
B. passed by the AP to the WLAN controller and then forwarded to the source PIM-enabled router，which creates an MGID table entry
C. passed by the AP to the WLAN controller， which creates an MGID table entry before forwarding to the directly connected PIM-enabled router
D. passed by the AP to its connected switch and then forwarded to the rendezvous point router，which creates an MGID table entry