MS-900 Describe cloud concepts 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.

• ✗

  Rapid elasticity

  Why it's wrong here

  Rapid elasticity is the ability to scale resources automatically (often based on demand) to meet fluctuating workloads, without manual intervention or pre-provisioning. In the scenario, the administrator manually adds or removes VMs via a web portal, which is a self-service action, not automatic scaling. The key distinction is that elasticity focuses on the system's internal autonomic scaling, whereas the scenario describes explicit user-initiated provisioning on demand.

• ✓

  On-demand self-service

  Why this is correct

  On-demand self-service is a cloud characteristic that allows consumers to provision and manage computing resources (e.g., VMs, storage) independently through a self-service portal or API, without requiring human interaction with the service provider. The scenario directly illustrates this: an administrator adds or removes VMs via a web portal, and the organization only pays for what they consume (consumption-based billing). This is the primary characteristic being demonstrated because the focus is on the user's ability to unilaterally change resources, not on the underlying metering or resource sharing.

• ✗

  Measured service

  Why it's wrong here

  Measured service refers to the cloud provider's ability to automatically monitor, meter, and report resource usage for billing and capacity planning, typically on a pay-as-you-go basis. While the scenario mentions consumption-based billing, measured service is a secondary characteristic that explains how the provider charges for the VMs; it does not describe the administrator's ability to self-provision. The primary action in the scenario is the user-initiated provisioning through the portal, not the metering mechanism. In other words, measured service is about the provider's telemetry, not the consumer's interactive control.

• ✗

  Resource pooling

  Why it's wrong here

  Resource pooling is a multi-tenant model where the provider's physical and virtual resources (compute, storage, network) are dynamically assigned and reassigned to serve multiple customers, creating economies of scale. The scenario does not mention any details about shared infrastructure, multi-tenancy, or location independence; it only describes an administrator's actions in a web portal. Resource pooling is an underlying architectural aspect of public clouds, but it is not the characteristic being demonstrated by the administrator's ability to add or remove VMs. The focus of the scenario is the user's direct control, not the provider's resource sharing.

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