In an 802.11n 2.4 GHz BSS, what prevents each station from using the full network bandwidth (e.g. 130 Mbps) for user data throughput when multiple clients are actively exchanging data with the AP?
A . Radio receiver hardware cannot process data as quickly as it can be transmitted.
B . Half of the bandwidth is allocated to uplink traffic and half to downlink traffic.
C . WLAN devices cannot detect collisions and must receive positive frame acknowledgment.
D . APs do not have sufficient wired connection speeds to the LAN, even at 1 Gbps connections with 802.11n and earlier APs.