What is a benefit of using a Cisco Wireless LAN Controller?

A Cisco Wireless LAN Controller centralizes access point management, which is the operational benefit described in option D. In a controller-based WLAN, lightweight APs join the WLC, download configuration, receive policy, and tunnel or switch client traffic according to the deployment model. That removes the need to configure every AP independently, which is exactly the pain point a WLC is designed to solve in enterprise wireless. Option A is backwards because central management normally reduces repeated per-AP configuration. Option B is false because multiple WLANs can use similar authentication methods while still using different SSIDs and policies. Option C is not the best answer because WLCs manage lightweight APs; autonomous APs are independently configured and do not rely on the same controller model. CCNA 200-301 v1.1 Network Access expects candidates to understand controller-based wireless architecture and the role of APs versus WLCs. Reference: Cisco wireless controller and lightweight AP deployment documentation.