Question: What is the primary purpose of the ConsumedUnits AVP in the Online Charging System (OCS), as utilized by the Rating Function (RF)?
Option 1: To notify the subscriber of impending tariff switches
Option 2: To initialize counters for new service subscriptions
Option 3: To update counters and track pricing based on consumed service units since the last Tariff Request or Service Usage Query message
Option 4: To validate the integrity of transmitted AVP codes
Explanation: The ConsumedUnits AVP informs the RF about total service units consumed since the previous request, enabling accurate counter updates and price tracking for efficient billing and charging management.