An ecommerce application runs on Amazon EC2 instances behind an Application Load Balancer in an Auto Scaling group across multiple Availability Zones. The application stores transactions in a MySQL 8.0 database running on a large EC2 instance; performance degrades as load increases. The application has far more reads than writes. The company wants an automatically scaling, highly available database solution for unpredictable read workloads. Which solution meets these requirements?

Amazon Aurora is a fully managed, MySQL-compatible relational database that offers high performance and scalability. A Multi-AZ deployment ensures high availability and disaster recovery. Configuring Aurora Auto Scaling with Aurora Replicas directly addresses the need for an automatically scaling, highly available database solution for unpredictable read workloads, as replicas offload read traffic and scale based on demand. Amazon Redshift is a data warehouse solution, not optimized for transactional ecommerce applications. A single-node deployment would also be a single point of failure. Amazon RDS with a Single-AZ deployment and reader instances in a different AZ still relies on a single primary instance for writes, which would remain a bottleneck. Amazon ElastiCache for Memcached is an in-memory caching service, not a persistent transactional database, and EC2 Spot Instances are unsuitable for critical, persistent database workloads due to their ephemeral nature.