A company wants to monitor its AWS costs for a monthly financial review. The cloud operations team is designing an architecture in the AWS Organizations management account to query AWS Cost and Usage Reports for all member accounts. The team must run the query once a month and provide a detailed bill analysis. Which solution is the MOST scalable and cost-effective way to meet these requirements?

The correct solution leverages AWS Cost and Usage Reports (CUR) delivered to Amazon S3, which is then queried by Amazon Athena. CUR provides the most detailed billing data. Delivering reports to S3 is a standard, cost-effective, and scalable storage solution for large datasets. Athena is a serverless query service that allows direct querying of data in S3 using standard SQL, making it highly scalable and cost-effective for ad-hoc or monthly analysis without managing any infrastructure. Incorrect options: Using Amazon Kinesis adds unnecessary complexity and cost for a monthly analysis, as Kinesis is primarily for real-time streaming data. Amazon EMR is an expensive and complex solution for this use case, requiring cluster management. Enabling CUR for member accounts is less efficient for centralized analysis; it's better to enable it once in the management account to capture all consolidated billing data. Amazon Redshift is a data warehouse solution that requires provisioning and management, making it less cost-effective and scalable for monthly ad-hoc queries compared to Athena. Again, Kinesis is not suitable for monthly batch analysis. Amazon QuickSight is a business intelligence tool for visualization, not the primary analysis engine for raw CUR data, and would still require a data source like Athena or Redshift.