Question: In a Mobile Originated Activity for CS scenario, when a VLR receives a request from an MS with an IMSI record marked 'Location Information Not Confirmed in HLR', what action does the VLR take?
Option 1: The VLR ignores the request and proceeds with the original activity (e.g., MS originated call, Short Message).
Option 2: The VLR sends a 'Subscriber Data Retrieval' request to the MSC (Mobile Switching Center).
Option 3: The VLR performs an 'Authentication Request' directly with the UE.
Option 4: The VLR performs an 'Update Location' to the HLR.
Explanation: In a Mobile Originated Activity for CS scenario, if the Visitor Location Register (VLR) encounters an MS with unconfirmed location information in the Home Location Register (HLR), it initiates an 'Update Location' procedure to synchronize the location data. This ensures accurate routing of subsequent requests and maintains network integrity.