单项选择题
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.Modify User1 Mailbox properties
B.Create a New ActiveSync Mailbox Policy
C.Create a New Exchange ActiveSync Mailbox policy
D.Modify properties of Default Exchange ActiveSync Mailbox policy