A sales reporting application runs in a US Region. It uses a Regional Amazon API Gateway and AWS Lambda to generate on-demand reports from an Amazon RDS for MySQL database. The frontend is on Amazon S3 and served via CloudFront. Route 53 currently uses a simple routing policy to point to the API Gateway API. The company will expand to Europe soon, and more than 90% of database traffic is read-only. API Gateway and Lambda are already deployed in the new Region. Which design minimizes latency for users downloading reports?

The correct answer minimizes latency by leveraging an RDS cross-Region read replica and Route 53 latency-based routing. An RDS cross-Region read replica provides a low-latency, read-only copy of the database in the new European Region, which is ideal since over 90% of traffic is read-only. Latency-based routing in Route 53 directs users to the API Gateway endpoint in the AWS Region that provides the lowest latency, ensuring they access the closest available resources, including the local read replica. Using AWS DMS with a full load or full load plus CDC would replicate the database, but DMS is typically used for migrations or continuous synchronization, not primarily for creating a low-latency read replica for ongoing operations. While DMS can replicate, an RDS read replica is purpose-built for this use case and integrates seamlessly with RDS. Geolocation routing would direct users based on their geographic location, which is effective, but latency-based routing directly optimizes for the fastest connection, which is the primary goal for minimizing latency.