How should the administrator configure me credentials?

A network administrator plans to set up a WLAN on an Aruba Instant cluster. The WLAN uses WPA/WPA2 Enterprise security. The administrator wants no authenticate users locally on the cluster.

How should the administrator configure me credentials?
A . Add a user account for each employee to the cluster internal server database.
B . Import authorized device MAC addresses to the cluster.
C . Implement a shared secret or password in the cluster WLAN settings.
D . Set up an external RADIUS server for authorization.

Answer: D