AZ-900 Describe cloud concepts Practice Question
What is a key advantage of using Azure Availability Zones over a single data center deployment?
⚠ Common exam trap
Many candidates confuse Availability Zones (within a region) with Azure Regions (geographically separated), leading them to incorrectly select Option C about automatic cross-region replication.
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
✓
Protection against single data center failures with a 99.99% SLA
Azure Availability Zones are physically separate data centers within an Azure region, each with independent power, cooling, and networking. By deploying resources across multiple zones, you protect your application from a single data center failure, and Azure guarantees 99.99% VM uptime SLA when VMs are deployed across two or more zones. This is a key advantage over a single data center deployment, which would have no such cross-zone redundancy.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Resources deployed across Availability Zones are cheaper than single-zone deployment
Why it's wrong here
Deploying resources across Availability Zones does not reduce cost; in fact, it often increases it. Zone-redundant SKUs for services like Virtual Machines or SQL Database typically carry a premium over single-zone configurations. Additionally, cross-zone data transfer may incur networking charges. The primary driver for using Availability Zones is high availability, not cost savings, so this statement is incorrect.
- ✓
Protection against single data center failures with a 99.99% SLA
Why this is correct
Availability Zones are physically separate datacenters within an Azure region, each with independent power, cooling, and networking. By deploying critical resources across multiple zones, you protect against a single datacenter failure—if one zone goes down, the others remain operational. Azure provides a financially backed 99.99% SLA for zone-redundant deployments, ensuring that your application stays available even during a localized outage. This is a core benefit of using Availability Zones.
- ✗
Resources are automatically replicated to a secondary Azure region
Why it's wrong here
Availability Zones are located within a single Azure region, providing resilience against datacenter failures in that region—not against entire region failures. Automatic replication to a secondary Azure region is a separate capability, such as Azure Paired Regions or geo-redundant storage, and is not provided by Availability Zones alone. Deploying across zones does not create any cross-region redundancy. Therefore, the statement that resources are automatically replicated to a secondary region is incorrect.
- ✗
Availability Zones eliminate the need for load balancing
Why it's wrong here
Availability Zones do not eliminate the need for load balancing; rather, they rely on it. Zone-redundant deployments require a load balancer to distribute incoming traffic across healthy instances in different zones. Without load balancing, you might have uneven traffic distribution, fail to reroute requests after a zone failure, or create a single point of entry. Load balancers work in conjunction with Availability Zones to ensure traffic is routed effectively and resiliently, so this option is wrong.
Go deeper
Related to this question
Learn chapter
High Availability and Scalability
Key term
Region
A region is a distinct geographic location where a cloud provider operates multiple data centers that are connected by low-latency networks and provide cloud services.
Key term
Availability
Availability is the measure of how often a system or service is operational and accessible when needed, typically expressed as a percentage of uptime.
About these practice questions
One of 981 original AZ-900 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. 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-900 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-900 exam.