A production environment currently runs on a single EC2 instance that hosts both the web application and a MariaDB database. Company policy mandates high availability for production systems. Which design change will bring this environment into compliance?

The correct option ensures high availability for both the application and the database. Migrating the database to an Amazon RDS for MariaDB Multi-AZ DB instance provides automatic failover and data replication across Availability Zones (AZs). Running the application on EC2 instances within an Auto Scaling group across multiple AZs, fronted by a load balancer, distributes traffic and automatically replaces unhealthy instances, preventing a single point of failure. The second option is incorrect because converting to Lambda might require significant re-architecture and Lambda itself is highly available by design, not by a "Multi-AZ option." The third option is incorrect as it relies on manual failover logic (Lambda launching instances) and doesn't provide continuous high availability or automatic data synchronization for the database. The fourth option is incorrect because a "stopped" standby database instance is not highly available; it requires manual intervention to start and doesn't offer automatic data replication or failover.