An application that is hosted on Amazon EC2 has a steady and consistent workload. The application will operate for at least 1 year. What is the MOST cost-effective instance purchasing option to meet these requirements?

For a steady, consistent workload that will run for at least a year, Reserved Instances (RIs) offer the most significant discount compared to On-Demand pricing. By committing to a 1-year or 3-year term, the company can achieve savings of up to 72%. This purchasing option is specifically designed for applications with predictable usage, making it the most cost-effective choice for this scenario. While Savings Plans also offer similar discounts for commitment, RIs are a direct and correct answer provided in the options.

A. Spot Instances are for workloads that can tolerate interruption and are not suitable for a steady application that must run continuously.
C. On-Demand Instances are flexible but are the most expensive option for long-term, predictable workloads.
D. Dedicated Hosts are for addressing compliance or software licensing needs and are typically more expensive than other options.

1. Amazon EC2 Documentation. (n.d.). Instance purchasing options. AWS. Retrieved from https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/instance-purchasing-options.html (See the "Reserved Instances" section, which states, "Reserved Instances provide you with a significant discount (up to 72%) compared to On-Demand Instance pricing.").

2. Amazon EC2. (n.d.). Amazon EC2 Reserved Instances. AWS. Retrieved from https://aws.amazon.com/ec2/pricing/reserved-instances/ (The page details how RIs are ideal for applications with steady state usage).

3. Amazon EC2. (n.d.). Amazon EC2 Pricing. AWS. Retrieved from https://aws.amazon.com/ec2/pricing/ (This page compares the use cases for On-Demand, Savings Plans, Reserved Instances, and Spot Instances).