What type of cloud service model provides a platform allowing developers to build applications?

The correct choice is Platform as a Service (PaaS). This cloud service model is specifically designed to provide a platform that allows developers to create, deploy, and manage applications without the complexity of building and maintaining the underlying infrastructure associated with developing and launching those applications.

In a PaaS environment, developers can focus on writing code and developing applications, while the cloud provider manages the hardware, operating systems, storage, and networking necessary for supporting those applications. PaaS solutions often include a variety of tools, such as development frameworks, databases, and middleware services, to enhance the development process and improve productivity.

This stands in contrast to Software as a Service (SaaS), which delivers software applications over the internet without the need for local installation, and Infrastructure as a Service (IaaS), which offers virtualized computing resources over the internet. Additionally, Container as a Service (CaaS) provides a way to manage and deploy containerized applications, lessening the abstraction that PaaS provides regarding underlying hardware and software management.

Overall, PaaS is key for developers looking for a streamlined application development environment that abstracts the complexities of infrastructure management.