You support a customer whose network environment includes Microsoft Lync Server 2013. A user
reports that when he attempts to dial out to a public switched telephone network (PSTN) number,
he receives the following message: “Your organization does not support calling this number.” All
other users are able to call the same number. You verify that the user is able to dial other Lync users
in the network. You need to ensure that the user is able to dial out to PSTN numbers. What should
you do?

A.
Modify the voice policy for this user for PSTN usage.

B.
Make sure the session initiation protocol (SIP) provider is sending the invite to a Mediation Server.

C.
Open outbound TCP port 5061 on the user’s computer.

D.
Change the associated normalization rule in the dial plan policy.