AZ-204 Develop Azure compute solutions Practice Question

You are developing a web application that allows users to upload images. The application is deployed on Azure App Service. After upload, the images must be processed to generate thumbnails and to extract metadata. The processing should happen asynchronously and must be resilient to failures. You need to design the solution using serverless components. The solution must minimize latency for the user during upload, and the processing must be retried automatically if it fails. You also need to ensure that the processing is idempotent, so that duplicate messages do not cause duplicate thumbnails. Which approach should you use?

Option A: Use Azure Functions with a Blob Storage trigger to process each image as it is uploaded. The function generates thumbnails and stores metadata in Cosmos DB. Use the `leaseBlob` property to prevent duplicate processing. Option B: Use Azure Functions with an Event Grid trigger to process images. The function generates thumbnails and stores metadata in Cosmos DB. Use Event Grid's built-in retry policy and idempotent logic in the function. Option C: Use Azure Logic Apps with a Blob Storage connector to process images. The logic app generates thumbnails and stores metadata in Cosmos DB. Configure retry policy on the connector. Option D: Use Azure Functions with a Service Bus queue trigger. The web app sends a message to the queue after upload. The function processes the message, generates thumbnails, and stores metadata. Use message deduplication to ensure idempotency.