The correct answer is: Migrate the databases to Amazon Aurora Serverless for Aurora MySQL.

Amazon Aurora Serverless (for Aurora MySQL) is a fully managed database service that automatically scales compute capacity up or down based on traffic patterns. It removes the need to manage servers, replication, failover, or capacity planning. Aurora offers high performance and durability and is compatible with MySQL, making the migration process straightforward. It is specifically designed for workloads with unpredictable or variable traffic, which makes it ideal for this use case.

Why the other options are incorrect:

Migrating to Aurora Serverless for Aurora PostgreSQL is not suitable because the current workloads are MySQL-based. Migrating to PostgreSQL would involve changing database engines and likely modifying application code, which contradicts the requirement for minimal effort.

Combining the databases into one larger MySQL database and running it on larger EC2 instances increases complexity and risk. It does not solve the core problem of manual scaling and introduces a single point of failure with a large, monolithic instance.

Creating an EC2 Auto Scaling group for the database tier is not feasible. Databases do not typically scale horizontally using EC2 Auto Scaling the way stateless applications do. You would still need to manually manage replication, synchronization, and failover between nodes.

Why this question is important: It evaluates your ability to transition from traditional, self-managed environments to fully managed, serverless services that scale dynamically and reduce operational overhead. Recognizing when Aurora Serverless is appropriate is a key skill in modern cloud-native architecture.

Tip: When an organization wants to reduce database management overhead while gaining scalability and durability, Aurora Serverless is often the right solutionespecially when staying within the same database engine family.

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