AZ-900 Practice Test 9 — 10 Questions

Question 1

A startup is building a mobile app backend and wants to use cloud services. They want to focus entirely on writing code and deploying features without worrying about server maintenance, operating system patches, or scaling infrastructure. Which cloud service model best fits this requirement?

Accepted Answer

Platform as a Service (PaaS). Platform as a Service (PaaS) is the correct model because it abstracts the underlying infrastructure, including servers, operating systems, and scaling, allowing developers to focus solely on writing code and deploying features. Azure App Service is a prime example of PaaS, providing built-in load balancing, auto-scaling, and patching without developer intervention.

Answer

Infrastructure as a Service (IaaS)

Answer

Software as a Service (SaaS)

Answer

Function as a Service (FaaS)

Question 2

A web application needs to store large amounts of unstructured data (images, documents) that will be accessed via HTTP from anywhere in the world. The data must be highly durable and scalable. Which Azure storage solution is most appropriate?

Accepted Answer

Azure Blob Storage. Azure Blob Storage is designed for storing massive amounts of unstructured data, such as images and documents, and provides HTTP/HTTPS access from anywhere. It offers high durability (99.9999999999% with RA-GRS) and massive scalability, making it the ideal choice for globally accessible, unstructured data workloads.

Answer

Azure SQL Database

Answer

Azure File Storage

Answer

Azure Cosmos DB

Question 3

An international e-commerce company has deployed its web application in two Azure regions to serve customers globally. The solution must automatically route users to the region with the lowest latency, provide high availability with automatic failover if one region becomes unavailable, and protect the application from common web exploits such as SQL injection and cross-site scripting at the edge. Which Azure service should the company use?

Accepted Answer

Azure Front Door. Azure Front Door is a global, scalable entry point that provides HTTP(S) load balancing with latency-based routing, automatic failover across regions, and built-in web application firewall (WAF) protection against common exploits like SQL injection and cross-site scripting. It operates at Layer 7 (application layer) and integrates with Azure WAF policies at the edge, making it the correct choice for this scenario.

Answer

Azure Traffic Manager

Answer

Azure Load Balancer

Answer

Azure Application Gateway

Question 4

An Azure service guarantees 99.95% uptime for virtual machines deployed with two or more instances in an availability set. If the monthly uptime falls below this percentage, customers can receive a service credit. What does this guarantee represent?

Accepted Answer

Service Level Agreement (SLA). This guarantee is a Service Level Agreement (SLA) because it is a formal, published commitment from Microsoft regarding the uptime percentage (99.95%) for a specific Azure service (Virtual Machines in an Availability Set), and it includes a financial remedy (service credits) if the commitment is not met. SLAs are contractual agreements that define the level of service a customer can expect and the compensation for failures.

Answer

Service Level Objective (SLO)

Answer

Service Level Indicator (SLI)

Answer

Service Health

Question 5

Which Azure region feature provides fault tolerance by isolating failures within a single region? It consists of physically separate datacenters with independent power, cooling, and networking.

Accepted Answer

Availability Zones. B is correct because Availability Zones are physically separate datacenters within an Azure region, each with independent power, cooling, and networking. This isolation ensures that if one zone fails, the others remain operational, providing fault tolerance within the same region. Availability Zones protect applications from datacenter-level failures, not just server or rack failures.

Answer

Availability Sets

Answer

Region Pairs

Answer

Fault Domains

Question 6

Which Azure storage service is best suited for storing unstructured data such as images, videos, and log files?

Accepted Answer

Azure Blob Storage. Azure Blob Storage is designed for storing massive amounts of unstructured data, such as images, videos, and log files. It offers three types of blobs (block, append, and page) to optimize for different access patterns, making it the ideal choice for binary and text data that does not fit a relational schema.

Answer

Azure Files

Answer

Azure Queue Storage

Answer

Azure Table Storage

Question 7

A startup wants to migrate its application to Azure. The development team needs to be able to provision virtual machines and storage on demand without waiting for manual approval from a central IT team. Which characteristic of cloud computing directly fulfills this requirement?

Accepted Answer

On-demand self-service. B is correct because on-demand self-service allows users to provision cloud resources like virtual machines and storage automatically, without requiring human interaction or manual approval from a central IT team. This characteristic is defined by NIST SP 800-145 as the ability for a consumer to unilaterally provision computing capabilities as needed, which directly matches the startup's requirement for no-wait provisioning.

Answer

Measured service

Answer

Rapid elasticity

Answer

Resource pooling

Question 8

A retail company runs its e-commerce platform on a public cloud. During a major sale event, they want to ensure that the application remains accessible even if an entire data center fails. Which cloud computing concept does this describe?

Accepted Answer

High availability. Option C is correct because high availability ensures that the application remains accessible even if an entire data center fails, typically through redundant infrastructure across multiple availability zones. This is achieved by deploying the application in a load-balanced, multi-AZ configuration that automatically fails over to healthy instances, maintaining uptime despite a complete data center outage.

Answer

Scalability

Answer

Elasticity

Answer

Disaster recovery

Question 9

A startup wants to use a cloud-based email service without installing any software on their own computers. They access the service through a web browser and the provider manages all updates and maintenance. Which cloud service model does this represent?

Accepted Answer

Software as a Service (SaaS). This scenario describes Software as a Service (SaaS) because the startup is using a fully managed cloud-based email application accessed via a web browser, with no local installation required. The provider handles all updates, maintenance, and infrastructure, which is the defining characteristic of SaaS. Examples include Microsoft 365 or Google Workspace, where the consumer only uses the software without managing the underlying platform or infrastructure.

Answer

Infrastructure as a Service (IaaS)

Answer

Platform as a Service (PaaS)

Answer

Anything as a Service (XaaS)

Question 10

A startup runs a web application on Azure virtual machines. The application experiences sudden, short-lived spikes in traffic multiple times a day. The startup configures an autoscale rule that adds two additional VM instances when CPU usage exceeds 75% and removes them when CPU drops below 30%. This approach is designed to match resource consumption closely to demand. Which cloud computing characteristic does this scenario primarily demonstrate?

Accepted Answer

Elasticity. Elasticity is the ability of a cloud system to automatically scale resources up or down based on real-time demand. In this scenario, the autoscale rule dynamically adds two VM instances when CPU exceeds 75% and removes them when CPU drops below 30%, closely matching resource consumption to traffic spikes. This on-demand provisioning and de-provisioning of compute capacity is the defining characteristic of elasticity.

Answer

High Availability

Answer

Fault Tolerance

Answer

Durability