Clients using Cisco-LEAP and EAP-FAST authentication are having no problems logging on to the wirelessnetwork， but clients using PEAP are failing to log on. Which situation would result in this type of problem？（）

• A、The AAA server is set to accept both MS-CHAP v2 and GTC for PEAP authentication.
• B、Clients have been set to validate the server identity.
• C、Posture validation has not been enabled.
• D、Clients and server are not using certificates.