A corporate network includes a single Active Directory Domain Services (AD DS) domain. The AD DS infrastructure is shown in the following graphic.

When the Montreal site domain controller is offline, authentication requests for Montreal branch office users are sent to the Toronto site domain controller.

You need to ensure that when the Montreal Site domain controller is offline, authentication requests for Montreal branch of?ce users are sent to the Quebec City site domain controller.

What should you do?

A.
Create a site link bndge between the Montreal site and the Quebec City site.

B.
Enable the global catalog role on the Montreal site domain controller.

C.
Modify the Default Domain Policy Group Policy Object.

D.
Delete the Toronto-Montreal Site Link

Explanation:
http://technet.microsoft.com/en-us/library/cc733142(v=ws.10).aspx