Your network environment has Microsoft Exchange Server 2010 and Forefront Protection for Exchange Server (FPE).

Emails sent to and received from the Internet are delivered by Exchange 2010 Edge Transport servers. End users report that they receive Delivery Status Notifications (DSN) messages from emails they did not send. The DSN messages state that the emails were undeliverable.

You need to ensure that only valid DSN messages are delivered to end users from email messages that they send.

Which type of filter should you use on the Edge Transport servers?

A.
Backscatter

B.
Connection

C.
Recipient

D.
Sender