A company runs many workloads on AWS and uses AWS Organizations to manage its accounts. The workloads are hosted on Amazon EC2. AWS Fargate. and AWS Lambda. Some of the workloads have unpredictable demand. Accounts record high usage in some months and low usage in other months. The company wants to optimize its compute costs over the next 3 years. A solutions architect obtains a 6-month average for each of the accounts across the organization to calculate usage. Which solution will provide the MOST cost savings for all the organization's compute usage? A. Purchase Reserved Instances for the organization to match the size and number of the most common EC2 instances from the member accounts. B. Purchase a Compute Savings Plan for the organization from the management account by using the recommendation at the management account level. C. Purchase Reserved Instances for each member account that had high EC2 usage according to the data from the last 6 months. D. Purchase an EC2 Instance Savings Plan for each member account from the management account based on EC2 usage data from the last 6 months.