Which AWS service provides a relational database management system that is fully compatible with MySQL and PostgreSQL?

Explanations:

Amazon DynamoDB is a fully managed NoSQL database service that does not support relational databases like MySQL or PostgreSQL. It is designed for applications that require high scalability and performance but does not offer SQL-based relational database features.

Amazon Aurora is a relational database service that is fully compatible with MySQL and PostgreSQL. It provides the performance and availability of high-end commercial databases at a lower cost. Aurora is designed to be cloud-native, offering features like auto-scaling and high durability.

Amazon Neptune is a fully managed graph database service that supports both property graph and RDF graph models. It is not compatible with traditional relational databases like MySQL or PostgreSQL, focusing instead on graph-based queries and relationships.

Amazon Athena is an interactive query service that allows users to analyze data in Amazon S3 using standard SQL. It is not a relational database management system and does not provide compatibility with MySQL or PostgreSQL. Instead, it enables querying data directly from S3 without needing to set up a database.