Question: In Mobile Terminating (MT) Closed User Group (CUG) handling, what action does the Gateway Mobile Switching Center (GMSC) take with CUG information received from the Home Location Register (HLR) during call establishment?
Option 1: The GMSC ignores the CUG information from the HLR and proceeds with the initial call setup.
Option 2: The GMSC uses both the initially received and HLR-provided CUG information for redundant verification.
Option 3: The GMSC continues the call establishment using the CUG information received from the HLR, overriding any initial CUG information.
Option 4: The GMSC sends the HLR's CUG information back to the originating network for further validation.
Explanation: In MT CUG handling, the GMSC prioritizes the CUG information provided by the HLR over any initial CUG details, ensuring the most authoritative and up-to-date subscription information guides the call establishment process, enhancing security and access control within closed user groups.