Question: What is required for a UE to obtain a local emergency PDN connection in the serving PLMN?
Option 1: The UE and PLMN must have compatible IP address versions, and the PDN GW must support only PDN type IPv4.
Option 2: The UE and PLMN must have compatible IP address versions, and the PDN GW associated with the emergency APN shall support both PDN type IPv4 and PDN type IPv6.
Option 3: The UE and PLMN must have incompatible IP address versions, and the PDN GW must support only PDN type IPv6.
Option 4: The UE and PLMN must have compatible IP address versions, but the PDN GW is not required to support any specific PDN type.
Explanation: In order for a UE to obtain a local emergency PDN connection in the serving PLMN, it is necessary that the UE and PLMN have compatible IP address versions. Additionally, the PDN GW associated with the emergency APN must support both PDN type IPv4 and PDN type IPv6, as specified in clause 5.3.1. This ensures that the UE can establish a connection using either IPv4 or IPv6, depending on its capabilities and the network's configuration.