AZ-900 Describe cloud concepts Practice Test 18 — 15 Questions

Question 1

What does 'high availability' mean in the context of cloud computing?

Accepted Answer

A system's ability to remain operational with minimal downtime. High availability in cloud computing refers to a system's ability to remain operational and accessible with minimal downtime, typically measured in terms of uptime percentage (e.g., 99.99% availability). This is achieved through redundant infrastructure, failover mechanisms, and service-level agreements (SLAs) that guarantee a certain level of continuity. Option B directly captures this core definition, distinguishing it from other cloud concepts like scalability or geo-replication.

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The ability to deploy resources globally across multiple regions

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The ability to automatically scale resources based on demand

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Storing data in multiple geographic locations

Question 2

Which of the following is an advantage of cloud computing related to speed of deployment?

Accepted Answer

Resources can be provisioned in minutes rather than weeks. Cloud computing enables rapid provisioning of resources through self-service portals and automation, allowing virtual machines, storage, and networks to be deployed in minutes via APIs or management consoles. This contrasts with on-premises environments where hardware procurement, racking, and configuration can take weeks. The speed of deployment is a core agility benefit of the cloud, directly supporting faster time-to-market for applications.

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You never need to patch operating systems

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You own the physical hardware

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All data is automatically encrypted at rest

Question 3

What is the primary difference between CapEx (Capital Expenditure) and OpEx (Operational Expenditure) in the context of IT spending?

Accepted Answer

CapEx requires large upfront investment in physical assets; OpEx is pay-as-you-go spending. CapEx involves a significant upfront investment in physical IT assets like servers, storage, and networking equipment, which are then depreciated over their useful life. OpEx, in contrast, aligns with cloud services where you pay only for what you consume (e.g., per-hour VM usage, per-GB storage), with no large initial outlay. This fundamental shift from owning to renting infrastructure is a core concept in Azure and cloud computing.

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CapEx is recurring monthly spending; OpEx is a one-time purchase

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CapEx is tax-deductible immediately; OpEx is depreciated over years

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CapEx and OpEx are identical for cloud services

Question 4

A startup wants to use cloud services to launch their product quickly without investing in hardware. Which cloud benefit does this BEST describe?

Accepted Answer

Agility and speed to market. The startup's need to launch quickly without upfront hardware investment directly maps to the cloud benefit of agility and speed to market. Azure's pay-as-you-go model and instant provisioning of virtual machines (e.g., Azure VMs) or platform services (e.g., Azure App Service) eliminate procurement delays, allowing deployment in minutes rather than weeks. This is the core value proposition of cloud computing for rapid product iteration.

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Fault tolerance

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Disaster recovery

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Geographic distribution

Question 5

What does the term 'fault tolerance' mean in cloud computing?

Accepted Answer

The ability to continue operating despite component failures. Fault tolerance is the ability of a system to continue operating without interruption when one or more of its components fail. In Azure, this is achieved through redundancy at multiple layers—such as using Availability Zones or redundant hardware—so that a failure in a single server, network path, or power supply does not bring down the entire workload. This is distinct from high availability, which focuses on minimizing downtime, whereas fault tolerance aims for zero downtime even during failures.

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The ability to scale resources up and down automatically

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The ability to recover data after accidental deletion

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The ability to deploy applications across multiple regions

Question 6

Which of the following statements accurately describes the shared responsibility model for SaaS applications?

Accepted Answer

The provider manages everything; the customer manages only data and user access. In the shared responsibility model for SaaS (Software as a Service), the cloud provider is responsible for the entire underlying infrastructure, including the application, runtime, operating system, and physical security. The customer's responsibilities are limited to managing their own data, configuring user access, and ensuring proper usage of the application. This model maximizes the provider's control, minimizing the customer's operational overhead.

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The customer manages the application, runtime, and operating system

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The customer and provider share equal responsibility for all components

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The customer manages the runtime and middleware

Question 7

A company operates on-premises servers that they own. They are considering moving to Azure. Which cloud benefit would MOST directly reduce their total cost of ownership?

Accepted Answer

Eliminating hardware purchase and maintenance costs. Moving to Azure eliminates the need to purchase, maintain, and eventually replace physical servers, which directly reduces capital expenditure (CapEx) and operational costs related to hardware lifecycle management. This is the most direct way to lower total cost of ownership (TCO) when transitioning from on-premises infrastructure to a public cloud model.

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Automatic compliance with all regulations

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Guaranteed zero downtime for all services

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Free support for all Azure services

Question 8

Which term describes the cloud's ability to quickly provision and de-provision resources to meet demand without human intervention?

Accepted Answer

Elasticity. Elasticity is the correct term because it specifically refers to the cloud's ability to automatically scale resources up or down in response to fluctuating demand, without requiring manual intervention. This is a core characteristic of cloud computing, enabling dynamic provisioning and de-provisioning of compute, storage, or network resources based on real-time metrics like CPU utilization or request count.

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High availability

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Fault tolerance

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Disaster recovery

Question 9

What is a key characteristic of the public cloud model?

Accepted Answer

Resources are shared among multiple tenants over the internet. The public cloud model is defined by multi-tenancy, where computing resources such as virtual machines, storage, and networks are shared across multiple customers (tenants) over the internet. Microsoft Azure, AWS, and Google Cloud all operate on this principle, using hypervisor-level isolation to ensure each tenant's data and workloads remain separate. This shared infrastructure enables the cloud provider to achieve economies of scale, offering pay-as-you-go pricing and elastic scalability.

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Resources are dedicated exclusively to one organization

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Resources are always hosted on-premises

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The organization owns all hardware

Question 10

A company's CTO asks why Azure can offer services at lower costs than building an equivalent on-premises solution. Which cloud principle BEST explains this?

Accepted Answer

Economies of scale. Economies of scale is the correct answer because cloud providers like Azure operate massive, standardized data centers that serve millions of customers simultaneously. This allows them to negotiate bulk discounts on hardware, power, and cooling, and to spread fixed operational costs across a vast customer base, resulting in per-unit costs far lower than what a single company would pay for an equivalent on-premises deployment.

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Elasticity

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High availability

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Geo-distribution

Question 11

Which statement BEST describes the benefit of cloud computing's 'predictable costs'?

Accepted Answer

Costs can be forecasted and controlled using consumption-based pricing and planning tools. Predictable costs in cloud computing refer to the ability to forecast and control spending through consumption-based pricing models (pay-as-you-go) and tools like Azure Cost Management + Billing. This allows organizations to estimate costs based on usage patterns, set budgets, and receive alerts, making financial planning more accurate compared to unpredictable capital expenses.

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You always pay the same amount regardless of usage

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Cloud services are always cheaper than on-premises solutions

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Hardware costs are fixed for the contract term

Question 12

A manufacturing company wants to process IoT sensor data locally at their factory floor to reduce latency before sending summarized data to the cloud. Which cloud computing concept does this represent?

Accepted Answer

Edge computing. Edge computing is the correct concept because it involves processing data near the source (the factory floor) rather than sending it to a centralized cloud data center. This reduces latency by performing initial analysis locally, with only summarized results transmitted to the cloud. The scenario explicitly describes local processing to minimize delay, which is the core purpose of edge computing.

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Hybrid cloud

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Public cloud

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Disaster recovery

Question 13

Which of the following is the cloud provider's responsibility under the shared responsibility model for Infrastructure as a Service (IaaS)?

Accepted Answer

Physical datacenter and host hardware. In the shared responsibility model for IaaS, the cloud provider is responsible for the physical infrastructure, including the datacenter, host hardware, network, and storage. This is because the customer has no physical access to these components and cannot manage them. The provider ensures the underlying hardware is maintained, secured, and operational.

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Operating system updates and patches

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Application data backup

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Network security group configuration

Question 14

What does the term 'scalability' mean in the context of cloud computing?

Accepted Answer

The ability to increase or decrease resources to match workload demand. Scalability in cloud computing refers to the ability to dynamically adjust computing resources—such as virtual machines, storage, or database throughput—up or down to match fluctuating workload demands. This is a core cloud characteristic that enables cost efficiency by paying only for what you use, and it is typically implemented through horizontal scaling (adding/removing instances) or vertical scaling (resizing an instance). In Azure, this is achieved via features like Virtual Machine Scale Sets or Azure App Service auto-scale rules.

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The ability to automatically recover from failures without data loss

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The ability to replicate data across multiple geographic regions

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The ability to deploy applications with no downtime

Question 15

A company is evaluating whether to move to cloud. Their IT manager says they are concerned about losing control over their data. Which Azure feature MOST directly addresses this concern?

Accepted Answer

Azure guarantees data never leaves the specified region unless configured to do so. Azure data residency controls, combined with Azure regions and data sovereignty guarantees, ensure that customer data stays within specified geographic boundaries. Microsoft's contractual commitments in the Microsoft Products and Services Data Protection Addendum (DPA) address data sovereignty concerns.

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Microsoft employees have unrestricted access to all customer data

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Data is automatically shared with government agencies

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All Azure data is stored in the United States