Your network contains one Active Directory forest named contoso.com.
The forest contains a single domain.
The domain contains the domain controllers is configured as shown in the following table.

The replication topology is configured as shown in the following output.

You discover that replication between DC1 and DC3 takes a few hours.
You need to reduce the amount of time it takes to replicate Active Directory changes between DC1 and DC3.
What should you do?
Correct Answer: D
Explanation/Reference:
Explanation:
Replication between DC1 and DC3 occurs via SiteLink4. By setting the cost of SiteLink4 to 100 will reduce the time it takes to replicate Active Directory changes between DC1 and DC3.
Site link cost can be used to determine which domain controller is contacted by clients in one site if the domain controller for the specified domain does not exist at that site. The client contacts the domain controller by using the site link that has the lowest cost assigned to it.
References:
https://docs.microsoft.com/en-us/windows-server/identity/ad-ds/plan/determining-the-cost