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.
Create a new ActiveSync Device Access rule.

B.
Create a new Exchange ActiveSync Mailbox policy.

C.
Modify the properties of User1’s mailbox.

D.
Modify the properties of the default Exchange ActiveSync Mailbox policy.