You have an Exchange 2010 organization.  Your companys security policy states that all connections to Outlook Web App （OWA） must use smartcard authentication.  You need to recommend a solution to meet the security policy requirements.  Which two possible ways to achieve this goal should you recommend？（）

• A、Require certificate-based authentication for all Internet-facing Client Access servers.
• B、Require Windows Integrated Authentication for all Internet-facing Client Access servers.
• C、Deploy an Edge Transport server， and then disable Windows Integrated Authentication.
• D、Deploy a server that runs Microsoft Internet Security and Acceleration （ISA） Server， and then enable Kerberos constrained delegation.