Exam AI-200 Topic 1 Question 3 Discussion

Use an Azure Event Grid trigger for event-driven processing of new blob uploads. Azure Blob Storage can publish events such as Microsoft.Storage.BlobCreated to Event Grid, which then pushes the event to the subscribed Azure Function or other event handler. This eliminates the need for the application to periodically scan the storage container for changes.
Microsoft distinguishes traditional polling-based Blob triggers from event-driven Blob/Event Grid processing . Event Grid-based processing provides low-latency, near-real-time delivery and supports high- scale workloads. Microsoft specifically notes that the Event Grid source eliminates polling delays and can process newly created blobs within seconds of upload.
A Timer trigger would explicitly introduce polling on a schedule. A Queue Storage trigger requires another component to place a message in a queue when the blob arrives, so it is not the direct event source described.
An HTTP trigger requires an external caller to invoke the function and therefore does not automatically react to a Blob Storage creation event.
Therefore, Event Grid is the correct trigger for automatic, low-latency, non-polling blob processing.
Study Guide references: Azure Functions # Event Grid triggers; Azure Blob Storage events; event-driven Blob processing; BlobCreated events; near-real-time processing.