Which S3 storage class meets these requirements MOST cost-effectively?

Explanations:

S3 Standard is designed for frequently accessed data and is more expensive than necessary for rarely accessed legacy data. Although it provides low latency, it does not meet cost-effectiveness requirements.

S3 One Zone-IA is cheaper than Standard but is not suitable for critical data that cannot be recreated, as it stores data in a single Availability Zone, which increases the risk of data loss. While it allows for retrieval within seconds, it doesn’t align with the need for high durability.

S3 Standard-IA is designed for infrequently accessed data and offers lower costs while ensuring data is still highly available. It provides rapid retrieval within seconds, making it the most cost-effective choice for critical, rarely accessed legacy data.

S3 Glacier is designed for archival storage and has retrieval times that can take minutes to hours, which does not meet the requirement of availability within seconds, making it unsuitable despite being cost-effective for long-term storage.