Question: What happens when the User Plane Function (UPF) receives an updated Packet Flow Description (PFD) from either the same or different Session Management Function (SMF) for the same application identifier?
Option 1: The UPF ignores the updated PFD and continues to use the existing one.
Option 2: The UPF merges the updated PFD with the existing one to create a new PFD.
Option 3: The latest received PFD overwrites any existing PFD stored in the UPF.
Option 4: The UPF sends a request to the Network Exposure Function (NEF) to verify the updated PFD.
Explanation: According to the text, when the UPF receives the updated PFD(s) from either the same or different SMF for the same application identifier, the latest received PFD(s) shall overwrite any existing PFD(s) stored in the UPF.