AWS Certified Cloud Practitioner — Question 517

A company plans to move its test workloads to Amazon EC2. The test workloads can be interrupted and are not required to start at a particular time.

Which EC2 instance purchasing option is MOST cost-effective for this use case?

Answer options

• A. On-Demand Instances:
• B. Spot Instances
• C. Reserved Instances
• D. Dedicated Hosts

Correct answer: B

Explanation

Spot Instances are the most cost-effective option for workloads that are flexible and can tolerate interruptions, offering up to a 90% discount compared to On-Demand prices. On-Demand Instances are more expensive and suited for continuous, uninterrupted workloads. Reserved Instances require a commitment term, which is unnecessary for highly flexible test workloads, and Dedicated Hosts are the most expensive option, used primarily for specific licensing or compliance needs.