A predictable workload runs across several AWS Regions using Lambda and On-Demand EC2 instances. The compute consumed in each Region fluctuates by user location. Which purchasing strategy should a SysOps admin use to reduce cost while accommodating regional variance?

Compute Savings Plans offer the most flexibility and cost savings for this scenario. They apply to Lambda and EC2 instances across any AWS Region, instance family, and operating system, making them ideal for fluctuating regional usage and mixed compute types. Buying based on the last 30 days of usage provides a good baseline for predictable workloads. EC2 Instance Savings Plans are less flexible as they commit to an instance family in a specific Region. Convertible and Standard Reserved Instances are also less suitable because they require commitments to specific instance types or families, and Standard RIs are tied to a specific Region, limiting their effectiveness for fluctuating regional usage and Lambda.