Your network contains an Exchange Server 2010 server.You need to prevent a user named User1 from downloading attachments larger than 50 KB when using Exchange ActiveSync.Your solution must not affect other users. 
What should you do first？（）

A.Exchange Control Panel （ECP）
B.Exchange Management Console （EMC）
C.Microsoft Office Outlook
D.Public Folder Management Console

A.Exchange Control Panel （ECP）
B.Exchange Management Console （EMC）
C.Microsoft Office Outlook
D.Public Folder Management Console

A.Mail enable Folder1.
B.Assign the author role to Anonymous.
C.Create a new mail contact that has the e-mail address folder1@contoso.com， and then create a transport rule.
D.Create a new mailbox that has the e-mail address folder1@contoso.com， and then create a transport rule.