A company runs a stateless web application with AWS Lambda functions invoked via Amazon API Gateway. The company wants Regional failover by deploying the application across multiple AWS Regions. What should a solutions architect do to route traffic across Regions?

The correct option is to create Amazon Route 53 health checks for each Region and use an active-active failover configuration. Route 53's DNS failover capabilities, combined with health checks monitoring the API Gateway endpoints, allow for automatic redirection of traffic to healthy regions. This provides a robust regional failover solution for stateless applications. Using an Amazon CloudFront distribution with an origin for each Region is not ideal because CloudFront is a CDN and while it can route traffic, its primary purpose is content delivery, not active-active regional failover for API Gateway. A transit gateway is designed for network connectivity between VPCs and on-premises networks, not for routing external HTTP/S traffic to API Gateway endpoints. An Application Load Balancer (ALB) is regional and cannot directly route traffic across multiple AWS Regions for high availability in this scenario; it would require a global load balancing solution like Route 53.