Spot Instances is the correct choice because these instances run on spare Amazon EC2 capacity at steep discounts and can be interrupted by AWS when that capacity is needed elsewhere, usually after a short notice period.

Spot Instances are designed for fault tolerant and flexible workloads such as batch processing and analytics where brief interruptions are acceptable. AWS reclaims the underlying capacity when demand rises and provides a short warning so you can checkpoint work or handle termination according to your chosen interruption behavior.

On-Demand Instances are not interrupted by AWS once they are running and you control when to stop or terminate them. They provide predictable availability and you pay for compute by the hour or second depending on the instance.

Standard Reserved Instances are a pricing option that gives a discount for committed usage and they do not change how or when AWS interrupts instances. They affect billing and not instance reclamation.

Convertible Reserved Instances offer discounted pricing with the flexibility to change instance attributes within certain rules and they are likewise a billing construct. They do not cause AWS to reclaim or interrupt your running instances.

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