单项选择题 Your company has a main office and a branch office. Your network contains a single Active Directory domain. An Active Directory site exists for each office. All domain controllers run Windows Server 2008  R2.   You plan to modify the DNS infrastructure.   You need to plan the new DNS infrastructure to meet the following requirements： èEnsure that the DNS service is available even if a single server fails èEncrypt the synchronization data that is sent between DNS servers èSupport dynamic updates to all DNS servers What should you include in your plan？（）

单项选择题 Your company has a main office and a branch office. The offices connect by using WAN links. The network consists of a single Active Directory domain. An Active Directory site exists for each office.   Servers in both offices run Windows Server 2008 R2 Enterprise.   You plan to deploy a failover cluster solution to service users in both offices.  You need to plan a failover cluster to meet the following requirements： èMaintain the availability of services if a single server fails èMinimize the number of servers required What should you include in your plan？（）

单项选择题 Your network consists of a single Active Directory domain. The network contains a file server that runs Windows Server 2008 R2. All servers use internal storage only. You plan to deploy a client/server application.   You need to deploy the application so that it is available if a single server fails. You must achieve this goal  while minimizing costs. What should you do？（）