多项选择题 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？（）

单项选择题 You have an Exchange Server 2010 organization. You deploy an Edge Transport server.  You need to implement a message hygiene solution that meets the following requirements： .Users must be able to receive e-mail from external recipients who have been added to their Safe SendersLists .The Edge Transport server must block all e-mail sent to invalid addresses inside the organization  What should you do first？（）

单项选择题 Your network contains two Exchange Server 2010 Edge Transport servers and five Exchange Server2010 Hub Transport servers.  All e-mail sent from your organization to the Internet is transferred by the Edge Transport servers. You need to recommend a security solution for the organization to meet the following requirements： .Ensure that users can send encrypted messages to any other organization on the Internet  .Ensure that all Exchange-related communication between Hub Transport servers and Edge Transport servers is encrypted What should you recommend？（）