A developer is building a high-performance web application that uses Amazon DynamoDB for its primary data store. The application experiences frequent read queries to a subset of its data, leading to increased latency and provisioned throughput consumption. The data is eventually consistent, and the application can tolerate slightly stale data for these read operations. Which AWS service or feature should the developer implement to reduce read latency and throughput costs?

Why the other options are wrong

• B. Amazon ElastiCache for Redis can be used as a general-purpose cache, but DAX is purpose-built and optimized for DynamoDB, offering simpler integration and better performance for DynamoDB-specific use cases.
• C. DynamoDB Global Tables provide multi-region replication for high availability and disaster recovery, not primarily for reducing read latency and costs within a single region for read-heavy workloads.
• D. DynamoDB On-Demand capacity mode adjusts throughput capacity automatically based on actual usage, which helps with cost efficiency for unpredictable workloads, but it doesn't directly reduce read latency like a cache.