Comprehensive and Detailed Explanation From SAP S/4HANA Cloud Public Edition, Management Accounting documents:

Event-Based Production Accounting replaces traditional period-end runs with financial postings triggered by actual business events.

Examples of these real-time postings include:

Work in Progress (WIP) calculation: WIP is calculated and posted at actual costs with each goods movement or confirmation, meaning the balance sheet is updated throughout the month rather than just at month-end.

Overhead calculation: Material and production overheads are charged immediately to the order as events occur, based on the costing sheet and event-based processing key.

Final goods receipt: This event triggers several simultaneous postings, including the credit of the production order with the delivery value, the clearing of WIP, and the automatic settlement of production variances.

Activity confirmation (Option C) is a business event that triggers these postings, but it is not a posting type itself.