Which EC2 instance type will meet these requirements?

Explanations:

Spot Instances are ideal for stateless workloads that can tolerate interruptions. They allow companies to bid on spare EC2 capacity, which can significantly reduce costs, making them a cost-effective option when current capacity isn’t fully utilized.

Dedicated Instances provide physical servers dedicated to a single customer, which incurs higher costs. They are not ideal for optimizing costs for stateless workloads when capacity is underutilized.

Reserved Instances require an upfront commitment for a specific instance type in a particular region over a one or three-year term. While they offer cost savings compared to On-Demand pricing, they do not provide flexibility for variable workloads, making them less suitable for optimizing costs in the scenario described.

On-Demand Instances allow companies to pay for compute capacity by the hour or second with no long-term commitments. However, they are more expensive than Spot Instances and do not take advantage of cost optimization for workloads that do not require constant capacity.