AZ-204 Practice Question: Connect to and consume Azure services and third-party services
You are building a solution that processes images uploaded to Azure Blob Storage. Each image must be analyzed by Azure AI Vision (Computer Vision). You need to trigger the analysis automatically when a new blob is created. Which Azure service should you use?
⚠ Common exam trap
It's easy for candidates to confuse Azure Event Grid as a standalone solution for executing code, when in fact it is only an event router that requires a subscriber (like Azure Functions) to perform the actual processing.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Azure Functions
Azure Functions is the correct choice because it provides a serverless compute service that can be triggered directly by Azure Event Grid when a new blob is created. This allows you to run custom code (e.g., calling Azure AI Vision APIs) in response to the blob storage event without managing infrastructure. The integration is native and efficient, with Event Grid delivering the event to the function via an HTTP trigger or Event Grid trigger binding.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Azure Event Grid
Why it's wrong here
Azure Event Grid is a highly scalable, fully managed event routing service that enables you to react to relevant events across Azure services and custom sources. While it can detect when an image is uploaded to Blob Storage and publish an event notification, Event Grid itself does not execute any processing logic on the image data. Its primary function is to deliver event notifications to subscribers, which then perform the actual work, making it unsuitable for directly processing images.
- ✗
Azure Logic Apps
Why it's wrong here
Azure Logic Apps provide a serverless platform for building automated workflows and integrating applications, data, and services using a visual designer. While a Logic App could be configured to trigger on a Blob Storage event and then use connectors or call an external API to process an image, it is generally less suitable for custom code-heavy computational tasks compared to Azure Functions. Its strength lies in orchestration and integration rather than raw code execution, making it a less efficient choice for direct image processing.
- ✓
Azure Functions
Why this is correct
Azure Functions is a serverless compute service that enables developers to run small pieces of event-driven code, known as "functions," without managing infrastructure. It offers native integration with Azure Blob Storage, allowing a function to be automatically triggered whenever a new image file is uploaded to a specified container. This makes Azure Functions an ideal and highly scalable choice for executing custom image processing logic, such as resizing, watermarking, or applying machine learning models, directly in response to the upload event.
- ✗
Azure WebJobs
Why it's wrong here
Azure WebJobs are a feature of Azure App Service that allows you to run background tasks, such as scripts or executables, within the context of an App Service web app. While WebJobs can be configured to monitor Azure Storage queues or blobs and perform processing, they are generally considered a legacy approach compared to Azure Functions. Functions offer a more robust serverless platform with superior scalability, a wider array of triggers and bindings, and a more streamlined development experience, making WebJobs a less optimal choice for modern event-driven processing solutions.
Quick reference
Azure Blob Storage Tier Comparison
| Tier | Storage Cost | Retrieval Cost | Latency | Use Case |
|---|---|---|---|---|
| Hot | Highest | Lowest | Immediate | Active data, frequent reads |
| Cool | Lower | Higher | Immediate | Data accessed < once / month |
| Cold | Lower still | Higher | Immediate | Data accessed < once / quarter |
| Archive | Lowest | Highest + rehydration delay | Hours | Long-term compliance retention |
Go deeper
Related to this question
Learn chapter
Azure Functions Development
Key term
Azure Event Grid
Azure Event Grid is a fully managed event routing service that allows applications and services to react to events in real time using a publish-subscribe model.
Key term
Durable Functions
Durable Functions is an extension of Azure Functions that lets you write stateful workflows in code, managing complex sequences of tasks, retries, and delays automatically.
About these practice questions
Courseiva writes every AZ-204 question from scratch — 881 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This AZ-204 practice question is part of Courseiva's free Microsoft certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the AZ-204 exam.