Explanation
Amazon ElastiCache is the correct choice because:
- In-memory data store: ElastiCache provides fully managed in-memory data stores using Redis or Memcached
- Open source compatibility: It supports popular open-source in-memory caching engines (Redis and Memcached)
- Managed service: AWS handles the operational overhead while maintaining compatibility with open-source APIs
Why other options are incorrect:
- Amazon DynamoDB: NoSQL database service, not primarily an in-memory data store
- Amazon Elastic Block Store (EBS): Block-level storage volumes for EC2 instances, not an in-memory data store
- Amazon Redshift: Data warehousing service for analytics, not an in-memory caching solution
ElastiCache is specifically designed for use cases requiring high-performance, low-latency in-memory caching with open-source compatibility.