AZ-204 Develop Azure compute solutions Practice Question
This AZ-204 practice question tests your understanding of develop azure compute solutions. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
You develop a serverless application using Azure Functions. The function must process images uploaded to a blob container. You need to ensure the function runs only when a new blob is created, and that it scales out automatically for high upload volumes. Which trigger and hosting plan combination should you use?
Correct. Blob trigger fires on new blobs, and Consumption plan scales out automatically to handle high volumes while charging only for execution time.
B
HTTP trigger + Consumption plan
Why wrong: Incorrect. HTTP trigger requires a client to send an HTTP request; it does not automatically respond to blob uploads.
C
Queue trigger + Consumption plan
Why wrong: Incorrect. This would require adding a separate process to write message to a queue after blob upload, increasing complexity and latency.
D
Timer trigger + Consumption plan
Why wrong: Incorrect. Timer trigger runs on a schedule and would process blobs based on time rather than actual upload events, leading to latency and inefficiency.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Blob trigger + Consumption plan
A Blob trigger is designed to run a function when a blob is created or updated in Azure Blob Storage, which directly matches the requirement to process images only when a new blob is uploaded. The Consumption plan provides automatic scaling based on demand, handling high upload volumes by dynamically allocating resources without manual intervention. This combination ensures event-driven execution and cost-effective scaling.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✓
Blob trigger + Consumption plan
Why this is correct
Correct. Blob trigger fires on new blobs, and Consumption plan scales out automatically to handle high volumes while charging only for execution time.
Related concept
Read the scenario before looking for a memorised answer.
✗
HTTP trigger + Consumption plan
Why it's wrong here
Incorrect. HTTP trigger requires a client to send an HTTP request; it does not automatically respond to blob uploads.
✗
Queue trigger + Consumption plan
Why it's wrong here
Incorrect. This would require adding a separate process to write message to a queue after blob upload, increasing complexity and latency.
✗
Timer trigger + Consumption plan
Why it's wrong here
Incorrect. Timer trigger runs on a schedule and would process blobs based on time rather than actual upload events, leading to latency and inefficiency.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates might confuse the Blob trigger with other triggers (HTTP, Queue, Timer) that can indirectly process blobs, but the question explicitly requires the function to run only when a new blob is created, which only the Blob trigger directly supports.
Detailed technical explanation
How to think about this question
Under the hood, the Blob trigger uses Azure Storage event subscriptions and the Blob Storage REST API to poll for new blobs, with a default polling interval of 10 seconds on the Consumption plan. For high upload volumes, the Consumption plan automatically scales out function instances based on the number of pending blob processing tasks, leveraging the Azure Functions scale controller. A subtle behavior is that the Blob trigger can occasionally process duplicate blobs due to internal retries or log scanning, so idempotent processing logic is recommended.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A startup's cloud architect reviews their monthly bill and notices costs are higher than expected for a long-running batch job. Switching from on-demand instances to Reserved Instances — or using Spot/Preemptible VMs — can reduce compute costs by up to 72 %. Questions like this test whether you understand the tradeoffs between commitment, flexibility, and cost across cloud pricing models.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this AZ-204 question in full detail.
Develop Azure compute solutions — This question tests Develop Azure compute solutions — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Blob trigger + Consumption plan — A Blob trigger is designed to run a function when a blob is created or updated in Azure Blob Storage, which directly matches the requirement to process images only when a new blob is uploaded. The Consumption plan provides automatic scaling based on demand, handling high upload volumes by dynamically allocating resources without manual intervention. This combination ensures event-driven execution and cost-effective scaling.
What should I do if I get this AZ-204 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
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.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.