A solutions architect is reviewing an application's resilience before launch. The application runs on an Amazon EC2 instance that is deployed in a private subnet of a VPC. The EC2 instance is provisioned by an Auto Scaling group that has a minimum capacity of I and a maximum capacity of I. The application stores data on an Amazon RDS for MySQL DB instance. The VPC has subnets configured in three Availability Zones and is configured with a single NAT gateway. The solutions architect needs to recommend a solution to ensure that the application will operate across multiple Availability Zones. Which solution will meet this requirement?