A recently acquired Cisco Aironet 1550 series AP is unable to join the WLC. This message is observed on the AP console:

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A recently acquired Cisco Aironet 1550 series AP is unable to join the WLC. This message is observed on the AP console:
AAA Authentication Failure for UserName:CC93.1981.0035 User Type: WLAN USER
Which action must be taken for the AP to associate with the controller?

A. Add MAC address CC93.1981.0035 to the Security:AAA:AP policy:Authorization List
B. Authenticate the AP to the WLC from the console using an admin account on the WLC.
C. Add MAC address CC93.1981.0035 to the Security:AAA:MAC Filtering tab.
D. Import the self-signed certificate of the AP to the Security:Certificate:LSC tab.
E. Import the self-signed certificate of the AP to the Security:Certificate:SSC tab. A