Question: In a Voice Group Call Service (VGCS) with RANflex configuration and group call redundancy, what is a required attribute for the lists stored in GCRs associated with MSCs within the same redundancy pool?
Option 1: A list of supported codecs for the voice group call, which may vary between GCRs.
Option 2: The identical list of cells inside the MSC area for the group call anchor MSC.
Option 3: The priority level related to the voice group call, which can be dynamically adjusted.
Option 4: The indication of uplink reply procedure applicability, dependent on the specific GCR.
Explanation: In a RANflex configuration with group call redundancy, having identical lists of cells inside the MSC area for the group call anchor MSC in all GCRs within the same redundancy pool is necessary to maintain consistency and prevent potential conflicts or gaps in service coverage during a voice group call.