A company needs to provision uninterruptible Amazon EC2 instances, when needed, and pay for compute...

On-Demand Instances are ideal for workloads that require flexibility, offering compute capacity with no upfront cost, allowing users to pay by the second for the instances they use. This makes it suitable for applications with short-term, spiky, or unpredictable workloads that cannot be interrupted. Reserved Instances require long-term commitments, Spot Instances can be interrupted, and Dedicated Instances are for specific hardware requirements, making On-Demand the correct choice for uninterruptible and flexible instance usage.