AWS Certified Solutions Architect – Professional — Question 986

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?

Answer options

• 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.

Correct answer: B

Explanation

Purchasing a Compute Savings Plan from the management account provides the highest savings and flexibility because it automatically applies to Amazon EC2, AWS Fargate, and AWS Lambda across all accounts in the AWS Organization. Utilizing recommendations at the management account level ensures the calculation considers the aggregated, fluctuating usage of all member accounts over the specified period. Reserved Instances and EC2 Instance Savings Plans are less optimal because they lack the flexibility to cover Fargate and Lambda, or they restrict savings to specific instance families and regions.