Question: What is the primary purpose of the Nhss_UECM_SNDeregistration service operation in a telecom network?
Option 1: To update the UE's context (e.g., IMEI change) in the HSS for EPS and/or PS services.
Option 2: To initiate a cancel location request to the Serving Node registered in HSS, serving the UE in EPS and/or PS.
Option 3: To retrieve the list of available PLMNs for a specific UE from the HSS.
Option 4: To register a new UE with the HSS for initial network access.
Explanation: The correct answer reflects the service operation's description, initiating a cancel location request. This is crucial in telecom networks for managing user equipment locations and ensuring efficient resource allocation when a UE is no longer active or needs to be deregistered from the current serving node. Options 1, 3, and 4 are incorrect as they describe different operations: updating UE context, retrieving available PLMNs, and new UE registration (opposite of deregistration).