Which AWS service helps deliver highly available applications with fast failover for multi-Region and Multi-AZ architectures?

Explanations:

AWS WAF (Web Application Firewall) is primarily used for protecting web applications from attacks, not for application availability or failover.

AWS Global Accelerator helps improve the availability and performance of applications with fast failover capabilities across multiple regions and availability zones.

AWS Shield is a managed DDoS protection service that safeguards applications, but it does not provide the multi-Region and Multi-AZ architecture support for application failover.

AWS Direct Connect is a service that allows a dedicated network connection from your premises to AWS, but it does not focus on application availability or failover.