Refer to the exhibit.

An engineer is troubleshooting this video conference issue:
A video call between a Cisco 9971 in Region1 and another Cisco 9971 in Region1 works.
As soon as the Cisco 9971 in Region1 conferences in a Cisco 8945 in Region2, the Region1 endpoint cannot see the Region2 endpoint video.
What is the cause of this issue?

Which two protocols are proxied over an Expressway-E/C pair when a MRA login including phone services is performed? (Choose two.)

A customer reports that the Cisco UCM toll-fraud prevention does not work correctly, and the customer is receiving charges for unapproved international calls as a result. Which two configuration changes resolve the issues? (Choose two.)

When a 8800 series phone is registered over MRA, where does it register?

Refer to the exhibit A user takes a phone from San Francisco to New York for a short reassignment. The phone was set up to use the San Francisco device pool, and device mobility is enabled on the Cisco UCM. The user makes a call that matches a route pattern in a route list that contains the Standard Local Route Group. To where does the call retreat?