Which solution will meet these requirements MOST cost-effectively?

Explanations:

While S3 Select allows querying data directly in S3, it does not provide a structured query capability for large datasets. Additionally, S3 Select does not help manage costs effectively over time, as it only allows access to the most current data without a scalable querying solution. Transitioning to S3 Glacier Deep Archive is suitable for compliance but does not address the query needs for ongoing analysis efficiently.

Amazon Redshift Spectrum is suitable for querying data in S3, but it incurs additional costs for using Redshift and may not be as cost-effective as other solutions for infrequent querying. The transition to S3 Glacier Deep Archive for data older than one year is appropriate for compliance, but the overall solution is less efficient and more costly due to Redshift management.

Using AWS Glue Data Catalog with Amazon Athena allows for efficient querying of unstructured data stored in S3. Athena is a serverless query service that can handle large datasets and is cost-effective for querying infrequently accessed data. Transitioning data older than one year to S3 Glacier Deep Archive meets compliance requirements while reducing storage costs for older data.

While Amazon Redshift Spectrum can query data in S3, the costs associated with Redshift may outweigh the benefits for this scenario, particularly when dealing with large amounts of data. S3 Intelligent-Tiering would not be as effective as S3 Glacier Deep Archive for long-term storage compliance, as it is designed for data with unpredictable access patterns and incurs ongoing storage costs.