Your network contains an Active Directory forest named contoso.com. The forest contains a
single domain and 10 domain controllers. All of the domain controllers run Windows Server
2008 R2 Service Pack 1 (SP1).
The forest contains an application directory partition named dc=app1, dc=contoso,dc=com.
A domain controller named DC1 has a copy of the application directory partition.
You need to configure a domain controller named DC2 to receive a copy of dc=app1,
dc=contoso,dc=corn.
Which tool should you use?

A.
Active Directory Sites and Services

B.
Dsmod

C.
Dcpromo

D.
Dsmgmt

Explanation:

http://technet.microsoft.com/en-us/library/cc732887.aspx
Dcpromo
Installs and removes Active Directory Domain Services (AD DS).
Parameter
ApplicationPartitionsToReplicate:””
Specifies the application directory partitions that dcpromo will replicate. Use the following
format:
“partition1” “partition2” “partitionN”
Use * to replicate all application directory partitions.
Original explanation:
Please Check Answer
I don’t think this is Dsmod. It is most likely Dcpromo.
Dsmod — Modifies an existing object of a specific type in the directory.