Question: For Mission Critical (MC) services, how can a UE (User Equipment) obtain the necessary Access Point Names (APNs) for SIP-1, HTTP-1, and CSC-1 reference points?
Option 1: Via dynamic allocation during each PDN connection setup.
Option 2: Exclusively through UE preconfiguration, without any option for update.
Option 3: Either via UE (pre)configuration or via initial UE configuration on a per HPLMN and optionally per VPLMN basis.
Option 4: By querying a public database of standardized APNs for MC services.
Explanation: This is correct because, according to the bearer management specifications for Mission Critical services, the UE can obtain the necessary APNs (for SIP-1, HTTP-1, and CSC-1 reference points) through either preconfiguration on the UE or through initial configuration provided by the network, which can vary based on the Home PLMN (HPLMN) and optionally the Visited PLMN (VPLMN). This approach ensures flexibility and accommodates different deployment scenarios while maintaining service integrity.