You have an Exchange Server 2013 organization named adatum.com.
You have a database availability group (DAG) that contains four Exchange servers named Server1,
Server2, Server3, and Server4. The file share witness is on a server named Share1.
The organization has two Send connectors. The Send connectors are configured as shown in the
following table.

Users report that email sent to external recipients is not being received.
You discover that outbound email messages are queued on Server3 and Server4.
You need to ensure that all of the email messages queued on Server3 and Server4 are delivered to
the Internet as quickly as possible.
What should you do?

A.
Modify the cost of External2.

B.
Disable External1.

C.
Modify the list of source bridgehead servers of External2.

D.
Modify the cost of External1.

Explanation:
Note:
* In Microsoft Exchange Server 2013, a Send connector controls the flow of outbound messages to
the receiving server.
* When a message is to be delivered to a remote delivery group, a routing path must be determined
for the message. Exchange 2013 uses the same logic as Exchange 2010 to select the routing path for
a message:
Calculate the least-cost routing path by adding the cost of the IP site links that must be traversed to
reach the destination. If the destination is a connector, the cost assigned to the address space is
added to the cost to reach the selected connector. If multiple routing paths are possible, the routing
path with the lowest aggregate cost is used;
If more than one routing path has the same cost, the routing path with the least number of hops is
used;
If more than one routing path is still available, the name assigned to the AD sites before the
destination is considered. The routing path where the AD site nearest the destination is lowest in
alphanumeric order is used. If the site nearest the destination is the same for all routing paths being
evaluated, an earlier site name is considered.