The correct answer is D. IaaS.
IaaS (Infrastructure as a Service) is a cloud computing service that provides virtual machines (VMs) over the internet. VMs are software-based emulations of physical computers that can be used to run applications and services. IaaS providers offer a variety of VM options, including different operating systems, CPU and memory configurations, and storage capacity.
CaaS (Compute as a Service) is a cloud computing service that provides access to computing resources, such as CPU, memory, and storage. CaaS providers offer a variety of compute options, including different types of processors, memory sizes, and storage capacities.
AaaS (Application as a Service) is a cloud computing service that provides access to applications that are hosted on the cloud provider’s infrastructure. AaaS providers offer a variety of applications, including productivity suites, customer relationship management (CRM) applications, and enterprise resource planning (ERP) applications.
PaaS (Platform as a Service) is a cloud computing service that provides a platform for developing, testing, and deploying applications. PaaS providers offer a variety of features, including a runtime environment, a database, and a web server.
In conclusion, IaaS is the only cloud computing service that relies on the virtual machine technology to deliver servers.