Explanation

VPC peering is the correct answer because:

• VPC peering allows you to connect two VPCs together, enabling them to communicate as if they were in the same network
• It supports inter-region VPC peering, which specifically allows VPCs in different AWS Regions to connect
• It uses the existing infrastructure of the VPCs without requiring additional hardware or complex configurations
• The traffic between peered VPCs stays within the AWS network and doesn't traverse the public internet

Why the other options are incorrect:

• AWS Client VPN: This is for connecting individual users/devices to AWS resources, not for VPC-to-VPC connectivity
• AWS Direct Connect: This establishes a dedicated network connection from on-premises to AWS, not for VPC-to-VPC connections across regions
• VPC endpoints: These provide private connectivity to AWS services, not for connecting VPCs together

Key Point: For connecting VPCs across different AWS Regions, inter-region VPC peering is the appropriate service that leverages existing VPC infrastructure.