Your network contains an Active Directory forest named contoso.com that contains a single domain. The forest
contains three sites named Site1, Site2, and Site3.
Domain controllers run either Windows Server 2008 R2 or Windows Server 2012 R2. Each site contains two
domain controllers. Site1 and Site2 contain a global catalog server.
You need to create a new site link between Site1 and Site2. The solution must ensure that the site link supports
the replication of all the naming contexts.
From which node should you create the site link?
To answer, select the appropriate node in the answer area.
Point and Shoot:
Answer: 
Explanation:
http://technet.microsoft.com/en-us/library/cc731294.aspxCan be done with SMTP link, but as this is one domain you must use IP Link. SMTP link only supports parent /
child domain scenarios
Active directory sites and services
\-> inter site transports
\->SMTP
SMTP is correct answer
From the link in the answer:
“Use the IP intersite transport unless your network has remote sites where network connectivity is intermittent or end-to-end IP connectivity is not available”.
IP is the correct answer. SMTP is rarely used today.
IP is the preferred protocol.
SMTP should be used for links that experience frequent outages.