You work as the enterprise exchange administrator at Company.com.The Company.com network consists of a single Active Directory domain named Company.com.Company.com has an Exchange Server 2010 organization.the Company.com contains three servers named -sr11， - sr12 and -sr13.-sr11 is configured as a mailbox server； -sr12 is configured as a client access server； and -sr13 is configured as a hub transport server.You have received complaints from the Company.com users that microsoft office outlook works very slowly.You need to find out the problem.What should you do？（）

• A、the best option is to run the performance monitor on -sr11 and -sr12 to gather the rpc performance data.
• B、the best option is to run the message tracking viewer on -sr11 and -sr12 to gather the rpc performance data.
• C、the best option is to run the exchange troubleshooting assistant on -sr11 and -sr12 to gather the rpc performance data.
• D、the best option is to run the mail flow troubleshooter on -sr12 and -sr13 to gather the rpc performance data.