AZ-900 Describe Azure architecture and services Practice Question

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 Container Instances

  Why it's wrong here

  Azure Container Instances (ACI) is incorrect because it allows you to run containers quickly without managing VMs, but it lacks the orchestration features needed for a multi-service microservices architecture. ACI does not provide built-in service discovery, automated rolling updates, or replica-based auto-scaling across multiple containers, so you would need to build those capabilities yourself or integrate an external orchestrator. This makes ACI suitable for simple, isolated workloads rather than full microservices orchestration.

  When this WOULD be correct

  A company needs to run a single container or a simple multi-container application quickly without managing VMs, and does not require advanced orchestration features like automatic scaling or rolling updates. For example, a batch processing job or a simple web app that can be restarted manually.

• ✓

  Azure Kubernetes Service (AKS)

  Why this is correct

  Azure Kubernetes Service (AKS) is the correct choice because it is a fully managed Kubernetes platform that offloads control plane management to Azure. It provides native container orchestration capabilities including automatic scaling, service discovery, rolling updates, self-healing, and load balancing—all essential for complex containerized microservices. AKS simplifies deploying and operating microservices at scale, making it the most appropriate service among these options.

• ✗

  Azure App Service

  Why it's wrong here

  Azure App Service is not the best fit because, while it can host containerized applications, it is fundamentally a PaaS service designed for web apps and APIs. App Service does not offer Kubernetes-grade orchestration features like pod scheduling, service-to-service discovery, or sophisticated rolling update strategies; it abstracts away the infrastructure but gives you less control over container placement and networking. Consequently, it works for simple containers but becomes limiting for complex, independently scalable microservices.

  When this WOULD be correct

  A company wants to deploy a web application using a Docker container with built-in auto-scaling and CI/CD support, but does not need advanced orchestration features like service discovery or rolling updates. They prefer a fully managed platform without managing VMs or Kubernetes clusters.

• ✗

  Azure Functions

  Why it's wrong here

  Azure Functions is incorrect because it is a serverless, event-driven compute service that executes short-lived code in response to triggers like HTTP requests or queue messages. It is not designed for running long-running containerized microservices, nor does it provide container orchestration with service discovery and rolling updates. Its scaling model is per-function and trigger-based, which does not match the operational requirements of a microservices architecture where each service manages its own lifecycle and networking.

  When this WOULD be correct

  A company needs to run event-driven code that responds to triggers (e.g., HTTP requests, queue messages) without managing infrastructure. The application is composed of small, stateless functions that scale automatically based on demand, and there is no requirement for container orchestration or rolling updates.

Option-by-option analysis

Why each answer is right or wrong

Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The AZ-900 exam frequently reuses these exact scenarios with slightly different constraints.

Analysis generated from the official AZ-900blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”