Which of the following best describes Infrastructure as a Service (IaaS)?

Infrastructure as a Service (IaaS) is primarily defined as a cloud service that provides virtualized computing resources over the internet. This includes essential components such as virtual machines, storage, and networks that businesses can use to run their applications and manage their workloads efficiently without the need to invest in physical hardware.

By utilizing IaaS, users can quickly scale their infrastructure to meet demand, reduce costs associated with maintaining physical servers, and leverage the flexibility of cloud computing. IaaS provides a foundational layer in cloud computing, enabling users to deploy and manage operating systems and applications while the cloud provider handles the infrastructure components.

The other options describe different types of cloud services. For example, one speaks about a platform that allows developers to build applications (which aligns more closely with Platform as a Service, or PaaS), while another option refers to software applications hosted on external servers, which is indicative of Software as a Service (SaaS). The mention of private networking pertains to specialized services often associated with IaaS but does not encompass the broader definition of IaaS itself.