You have an Exchange organization.All servers in the organization have Exchange Server 2010 Service Pack 1 （SP1） installed.You need to identify why a remote SMTP server rejects e-mail sent from the organization. What should you do？（）

• A、Modify the diagnostic logging level on the MSExchangeTransportService object， and then review the Application event log
• B、Modify the connectivity log settings on the Transport server， and then review the connectivity logs.
• C、Modify the message tracking settings on the Transport server， and then review the message tracking logs.
• D、Modify the protocol logging level on the Send connectors， and then review the protocol logs.