Question: Which entity initiates the update procedure for published service API information, such as changes in service API characteristics, towards the CAPIF core function?
Option 1: User Equipment (UE) via a mobile application
Option 2: Network Function (NF) within the PLMN trust domain
Option 3: API Publishing Function (within either PLMN or 3rd party trust domain)
Option 4: External Application Server using Northbound APIs
Explanation: The correct answer is Option 3 because the update procedure for published service API information is initiated by the API Publishing Function, which can reside within the Public Land Mobile Network (PLMN) trust domain or a third-party trust domain, managing and updating service APIs regardless of its location relative to the PLMN.