Your organization operates 150 D4as_v5 production VMs spread across three subscriptions. The workloads are expected to run steadily for at least three years. You need to maximize savings, apply discounts across subscriptions, and retain some flexibility if 10% of the fleet is retired midterm. What should you recommend?

The correct option maximizes savings for a stable, long-term workload across multiple subscriptions. Three-year Reserved VM Instances (RIs) offer the largest discount. A shared scope allows the RIs to apply to any eligible VM in any subscription under the billing account, ensuring full utilization and maximizing savings. The ability to cancel a portion of the reservation provides flexibility if a small percentage of VMs are retired, though cancellation fees and limits apply. Incorrect options: 1-year reservations with single-subscription scope are less cost-effective and don't allow cross-subscription application. While exchanges are possible, this option doesn't meet the primary goal of maximizing savings for a 3-year commitment. Compute Savings Plans offer flexibility but generally provide lower discounts than 3-year RIs for consistent workloads. Reservations scoped to individual resource groups limit flexibility and don't allow cross-subscription benefits. Unused amounts do not automatically convert to Azure credits. Spot VMs are for interruptible workloads and are unsuitable for production environments requiring high availability and predictable performance.