A company built a stateless two-tier application using Amazon EC2 in a single Availability Zone and an Amazon RDS Multi-AZ DB instance. New management wants the application to be highly available. What should a solutions architect do to meet this requirement?

To achieve high availability, the application needs to tolerate an Availability Zone (AZ) outage. The current setup is in a single AZ. Configuring Multi-AZ EC2 Auto Scaling ensures that EC2 instances are distributed across multiple AZs, providing redundancy for the application tier. An Application Load Balancer (ALB) is essential to distribute incoming traffic across these instances and automatically route around unhealthy instances or AZs. Sending EC2 snapshots to another region (B) is for disaster recovery, not high availability within the current region. Route 53 latency-based routing (C) is typically for global applications across regions, not for high availability within a single region. While Route 53 rules and a Multi-AZ ALB (D) are good components, this option doesn't address the core issue of the EC2 instances themselves being in a single AZ,