Which statement best describes clustering in a small-business wireless network？（）  

A、A. allows multiple access points to be connected wirelessly， without the need for a wired Ethernet network

B、B. replicates configuration parameters across access points in the cluster， while optimizing network performance

C、C. automatically configures wireless client devices via Wi-Fi Protected Setup

D、D. can get real-time traffic or bandwidth statistics from an access point within a cluster