Answer: Create a gateway VPC endpoint for Amazon S3. Associate this endpoint with all route tables in the VPC

## Explanation **Correct Answer: C** **Why Option C is correct:** 1. **Cost minimization**: Gateway VPC endpoints for S3 are free (no hourly charges or data processing fees). The only cost is the standard S3 data transfer and storage costs. 2. **Prevents internet traversal**: Gateway VPC endpoints allow traffic between the VPC and S3 to stay within the AWS network, avoiding the public internet. 3. **Route table association**: Associating the endpoint with all route tables ensures that all subnets in the VPC can use the endpoint. **Why other options are incorrect:** **Option A (S3 Intelligent-Tiering)**: - This is a storage class optimization feature that automatically moves data between access tiers based on access patterns. - It helps reduce storage costs but does NOT prevent traffic from traversing the internet. - The application still needs to access S3 over the internet unless combined with other networking solutions. **Option B (S3 Transfer Acceleration)**: - This feature uses CloudFront's edge locations to accelerate uploads to S3. - It actually routes traffic through the internet (via CloudFront edge locations), which contradicts the requirement to prevent internet traversal. - It may increase costs due to CloudFront data transfer charges. **Option D (Interface endpoint for Amazon S3)**: - Interface endpoints (AWS PrivateLink) are available for many AWS services, but for S3 specifically, gateway endpoints are the recommended and cost-effective solution. - Interface endpoints incur hourly charges and data processing fees, which would increase costs. - Gateway endpoints are specifically designed for S3 and are more cost-effective. **Key AWS Concepts:** - **Gateway VPC Endpoint**: A horizontally scaled, redundant gateway that allows private connectivity between VPC and supported AWS services (like S3) without requiring an internet gateway, NAT device, VPN connection, or AWS Direct Connect. - **Interface VPC Endpoint**: Uses AWS PrivateLink technology and provides private connectivity to services that support it, but typically incurs costs. - For S3 access from within a VPC, gateway endpoints are the most cost-effective solution for keeping traffic within AWS network. **Additional Considerations:** - The application processes 1 TB of data daily, so keeping this traffic within AWS network avoids potential internet bandwidth costs and improves security. - Gateway endpoints work with S3 bucket policies and IAM policies to control access. - This solution meets both requirements: minimizing costs (free endpoint) and preventing internet traversal (traffic stays within AWS network).