Correct answer: Provision a standard accelerator using AWS Global Accelerator. Create endpoint groups in both Regions and register each NLB as an endpoint in its respective group.

Explanation: AWS Global Accelerator provides global performance improvement and automatic traffic routing based on health and geographic proximity. It uses the AWS global network to route traffic to the closest and healthiest endpoint, significantly improving performance and availability for global applications like APIs. This setup avoids manual DNS management, simplifies failover, and reduces latency more effectively than any DNS-based solution alone.

Why the other options are incorrect:

Attaching Elastic IPs to individual EC2 instances and routing with Route 53 geolocation is operationally intensive, lacks automatic failover between instances or load balancers, and does not scale well.
Using latency-based routing with ALBs and CloudFront adds unnecessary complexity by replacing the existing NLBs and introducing CloudFront, which is better suited for caching content than routing low-latency, dynamic API traffic.
Configuring Route 53 geolocation routing with CloudFront adds a DNS-layer workaround rather than a robust, optimized solution. While this might help with region-aware routing, it lacks the intelligence and network-layer performance optimization provided by Global Accelerator.

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