Amazon S3 offers the ability to configure a lifecycle policy that can transition objects to a lower-cost storage class after a set period of time. In this case, storing files in S3 Standard for immediate and frequent access, then automatically transitioning them to S3 Standard-Infrequent Access (S3 Standard-IA) after 30 days, provides a cost-effective solution that still maintains reasonable access to the data when needed. Other options do not provide the same level of cost optimization aligned with the described access pattern, either lacking lifecycle management or being optimized for different access patterns.