Which setting provides the best security for a WLAN and authenticates users against a centralized directory store?

Which setting provides the best security for a WLAN and authenticates users against a centralized
directory store?

A.
WPA2 AES-CCMP and 801.X authentication

B.
WPA2 AES-CCMP and PSK authentication

C.
WPA2 TKIP and PSK authentication

D.
WPA2 TKIP and 802.1X authentication

Explanation: