A data analytics company receives thousands of small data files periodically via FTP. An on‑premises batch job currently processes them overnight, taking hours. The company wants the AWS solution to process incoming files as soon as possible with minimal changes to the FTP clients. The solution must delete files after successful processing. Each file's processing takes 3–8 minutes. Which solution meets these requirements with the MOST operational efficiency?

The correct solution uses AWS Transfer Family for an FTP endpoint, storing files directly in Amazon S3 Standard. S3 event notifications trigger an AWS Lambda function for each new file, enabling near real-time, serverless processing as soon as files arrive. Lambda is ideal for tasks taking 3-8 minutes, and it can delete the file after processing. This approach is highly operationally efficient because it's fully managed, scales automatically, and only incurs costs when files are processed. The first two incorrect options use EC2 instances running FTP servers, which requires managing servers and doesn't offer the operational efficiency of a managed service like AWS Transfer Family. They also suggest nightly processing, which contradicts the requirement for "as soon as possible" processing. The third incorrect option uses AWS Transfer Family but stores files on an EBS volume, which is less scalable and more complex to manage than S3 for this use case, and it doesn't leverage S3 event notifications directly for real-time processing.