Which service model provides users with virtualized computing resources over the internet?

The service model that provides users with virtualized computing resources over the internet is Infrastructure as a Service (IaaS). IaaS offers fundamental computing resources such as virtual machines, storage, and networks that clients can provision and manage over the internet. This model allows users to scale resources up or down according to their needs without having to invest in and maintain physical hardware.

With IaaS, users have greater flexibility and control over their computing environment, as they can deploy their own operating systems and applications on the virtualized resources provided. This contrasts with other service models like Software as a Service (SaaS), which delivers software applications via the internet without exposing the underlying infrastructure, and Platform as a Service (PaaS), which offers a platform for developers to build, test, and deploy applications without managing the underlying infrastructure.

Cloud Storage as a Service is not a recognized service model in the same way as the others mentioned, as it typically falls under the umbrella of IaaS or specialized storage solutions. Each of these service models serves different purposes, but IaaS is specifically designed for providing virtualized computing resources, aligning perfectly with the requirements stated in the question.