What runs on all Domain Controllers and creates and maintains replication topology?

What runs on all Domain Controllers and creates and maintains replication topology?

• Knowledge Consistency Checker
• DNS
• Schema Master
• LDAP 

EXPLANATION

The Knowledge Consistency Checker (KCC) is a built-in process that runs on all domain controllers and creates the replication topology for the forest. The KCC creates replication connections between domain controllers in the same site automatically.

SOURCE

https://technet.microsoft.com/en-us/library/cc961781.aspx