Question: What is the implication of having Network Slice Simultaneous Registration Group (NSSRG) information present in a UE's subscription information on the Allowed NSSAI?
Option 1: The AMF will allow any combination of S-NSSAIs to be simultaneously provided to the UE.
Option 2: The HPLMN will only send default S-NSSAIs to a non-supporting VPLMN as part of the subscription information.
Option 3: The NSSRG information is ignored by the AMF when evaluating the Requested NSSAI.
Option 4: The Allowed NSSAI for the UE can only include S-NSSAIs which share a common NSSRG.
Explanation: According to the text, if NSSRG information is present in the subscription information, at least one NSSRG shall be associated with each of the S-NSSAIs in the subscription information. This means that the AMF will only allow S-NSSAIs that share a common NSSRG to be simultaneously provided to the UE in the Allowed NSSAI.