A company runs workloads across many AWS accounts managed via AWS Organizations. Workloads include Amazon EC2, AWS Fargate, and AWS Lambda, and demand varies unpredictably across accounts. The solutions architect computed a 6-month average usage per account to estimate future usage. Which purchase option will yield the MOST cost savings for the organization's compute usage over the next 3 years?

A Compute Savings Plan offers the most flexibility and potential for cost savings across diverse compute services like EC2, Fargate, and Lambda, which is ideal for unpredictable, varied workloads across multiple accounts in an AWS Organization. By purchasing at the management account level for the entire organization, the Savings Plan automatically applies to eligible usage across all member accounts, maximizing utilization and savings. Using recommendations at the management account level ensures the plan is optimized for the aggregated usage patterns. Purchasing Reserved Instances (RIs) for specific EC2 instance types is less flexible as it doesn't cover Fargate or Lambda, and might lead to underutilization if instance types change. Purchasing RIs or EC2 Instance Savings Plans per member account is less efficient than an organizational Compute Savings Plan, as it fragments the commitment and reduces the ability to share unused capacity across accounts.