AWS Certified Cloud Practitioner (CLF-C02) — Question 448

A company runs Amazon EC2 instances in a research lab. The instances run for 3 hours each week and cannot be interrupted.

What is the MOST cost-effective instance purchasing option to meet these requirements?

Answer options

• A. Compute Savings Plan
• B. On-Demand Instances
• C. Convertible Reserved Instances
• D. Spot Instances

Correct answer: B

Explanation

On-Demand Instances are the most cost-effective option because the workload runs for only 3 hours per week and cannot tolerate interruptions, which eliminates Spot Instances. Both Compute Savings Plans and Convertible Reserved Instances require a commitment of 1 or 3 years, making them inefficient for such low-utilization workloads. Therefore, paying the standard hourly rate via On-Demand is the most economical choice.