A company has workloads that run in a VPC. The workloads access Amazon S3 by using an S3 gateway endpoint. The company also has on-premises workloads…

An S3 interface endpoint provides a private IP address within the VPC, making it accessible from on-premises networks over a VPN or Direct Connect. By configuring the on-premises DNS resolver to point S3 DNS names to the interface endpoint's private IPs, on-premises workloads can access S3 privately and transparently. This solution is the most operationally efficient as it avoids the need to deploy, manage, and scale a fleet of proxy instances. The existing S3 gateway endpoint can remain for VPC workloads, ensuring no disruption.

A. An S3 gateway endpoint is a route table target and is not accessible from on-premises over a VPN. Therefore, the proxy fleet could not be reached by on-premises workloads to access S3.
B. While using an interface endpoint is correct, this option unnecessarily adds the operational complexity and cost of managing a proxy fleet and an Application Load Balancer.
D. Setting up a Direct Connect with a public VIF is a complex and costly solution that is not required when a VPN connection already exists. It's not the most operationally efficient approach.

1. AWS PrivateLink Documentation. (n.d.). Access an AWS service using an interface VPC endpoint. AWS. Retrieved from https://docs.aws.amazon.com/vpc/latest/privatelink/vpce-interface.html (See section "On-premises access to an interface endpoint").

2. Amazon S3 Documentation. (n.d.). Accessing Amazon S3 using an interface endpoint (AWS PrivateLink). AWS. Retrieved from https://docs.aws.amazon.com/AmazonS3/latest/userguide/privatelink-interface-endpoints.html (Section explains how on-premises applications can use interface endpoints).

3. AWS Networking & Content Delivery Blog. (2019, August 8). How to use AWS PrivateLink to secure and scale on-premises access to Amazon S3. AWS. Retrieved from https://aws.amazon.com/blogs/networking-and-content-delivery/how-to-use-aws-privatelink-to-secure-and-scale-on-premises-access-to-amazon-s3/ (This blog post details the exact architecture described in the correct answer).