Exhibit： You work as a network administrator at.You study the exhibit carefully. Three different wireless groups of users （support， staff， guests） are permitted to access the wireless LAN.  Which security policy should be implemented for the users in the guests group？ （）

• A、LEAP authentication
• B、Primary SSID with open or no WEP authentication
• C、Static WEP and authentication
• D、Open authentication with WEP plus MAC authentication