Which EC2 instance purchasing option meets this requirement with the LARGEST discount compared to On-Demand prices?

Explanations:

Spot Instances provide the largest discount compared to On-Demand prices, often up to 90%. They are ideal for workloads that can tolerate interruptions since they can be terminated by AWS when demand increases.

Convertible Reserved Instances offer a discount over On-Demand prices, but the discount is generally less than that of Spot Instances. They require a commitment to a one- or three-year term but allow changes to the instance type.

Standard Reserved Instances also provide significant discounts compared to On-Demand pricing, typically ranging from 30% to 60%. However, they require a commitment for a longer term and do not offer the same level of pricing flexibility as Spot Instances.

Dedicated Hosts are used for compliance and licensing requirements rather than cost savings. They provide the least discount compared to On-Demand prices and require users to pay for the entire host, not just the instances they run.