Available to Promise (ATP) (C) in Oracle Fusion Cloud SCM ensures product availability commitments by calculating how much inventory is available for new orders based on current stock and supply constraints like production schedules and supplier lead times. For example, if 100 units are on hand with 40 committed, ATP shows 60 units available, ensuring accurate promises. Option A (Cost Accounting) tracks financials, not availability. Option B (Supplier Portal) supports collaboration, not direct commitment calculations. Option D (Manufacturing Execution) manages production, not order promising. ATP's real-time analysis prevents overpromising, aligning customer expectations with operational capacity.