Contoso., Ltd. has a network that contains a single Exchange Server 2003 server named Server1.
The e-mail address of each Contoso user has a contoso.com suffix.
Contoso and a company named Fabrikam, Inc. merge. Fabrikam has a separate Exchange organization that contains a single Exchange Server 2003 server named Exchange1.
Some users at Cuntoso and all users at Fabrikam must have an e-mail address that has a fabrikam.com suffix.
You assign fabrikam.com e-mail addresses to the appropriate Contoso users. You configure the Exchange organization as non-authoritative for the fabrikam.com domain.
You need to ensure that e-mail messages sent to users that have a fabrikam.com address are delivered to the correct recipients on Server1 and Exchange1.
What should you do?

A.
In the external DNS zone for fabrikam.com, configure an MX record that points to Exchange1.

B.
On Server1, create an SMTP virtual server that uses Exchange1 as a smart host.

C.
On Server1, configure the default SMTP virtual server to forward all e-mail messages that have unresolved recipients to Exchange1.

D.
On Server1, create a SMTP connector that has. a fabrikam.com address space. Configure the connector to allow relaying and to use Exchange1 as a smart host.