Which service provides virtualized computing resources over the internet?

Infrastructure as a Service (IaaS) is the correct answer because it specifically refers to the delivery of virtualized computing resources over the internet. IaaS provides essential elements such as virtual machines, storage, and networks to users, enabling them to run various applications without needing the physical hardware. This model allows businesses to rent the computing infrastructure they require, scaling resources as needed and enhancing flexibility while minimizing the capital expenditures associated with purchasing and maintaining physical servers.

The other alternatives serve different purposes in the cloud service model. Platform as a Service (PaaS) focuses on providing a platform allowing developers to build, deploy, and manage applications without dealing with the underlying infrastructure. Network as a Service (NaaS) pertains strictly to networking services, allowing users to provision and manage network resources rather than full computing resources. Software as a Service (SaaS) delivers software applications over the internet, eliminating the need for installations and maintenance on user devices, which is distinct from the infrastructure provisioning that IaaS offers. Each of these services plays a vital role in the cloud computing ecosystem, but IaaS uniquely provides the virtualized hardware resources needed for various workloads.