Question: When a 3GPP AAA Proxy receives a UE's Care of Address from a PDN GW in the Visited Public Land Mobile Network (VPLMN), what action may it take based on this information?
Option 1: Immediately update the UE's subscription profile to reflect the new location.
Option 2: Select a different PDN GW closer to the UE than the current one, as per specified network optimization protocols.
Option 3: Respond with a Result-Code set to DIAMETER_SUCCESS_RELOCATE_HA and include the selected PDN GW identity in the MIP6-Agent-Info AVP.
Option 4: Ignore the Care of Address and continue using the existing PDN GW for the UE's connection.
Explanation: This is the correct action because, upon receiving the UE Care of Address, if a more optimal PDN GW is selected based on this address, the proxy responds with a DIAMETER_SUCCESS_RELOCATE_HA Result-Code and includes the identity of the newly selected PDN GW in the MIP6-Agent-Info AVP, facilitating a seamless handover for improved network efficiency and user experience.