Question: How do network functions within the 5GC Control Plane interact with each other?
Option 1: Using only reference point representation.
Option 2: Using only service-based interfaces for their interactions.
Option 3: Using both service-based and reference point representations interchangeably.
Option 4: Using direct communication or indirect communication via the SCP.
Explanation: According to the text, network functions within the 5GC Control Plane shall only use service-based interfaces for their interactions. This is specified in clause 4.2.6 and ensures a standardized way of interaction between network functions.