A company is planning to deploy an application to a secure cloud environment. The solution must meet these requirements: - A third-party must control the underlying cloud infrastructure. - The…

SaaS (Software as a Service) would mean the third-party controls everything, including the applications, which contradicts the requirement for the company to control its deployed applications.

IaaS (Infrastructure as a Service) would require the company to control not only the applications but also the operating systems, middleware, and runtime environments, which goes beyond the specified requirement of only controlling deployed applications.

Platform as a Service (PaaS) is a cloud computing service model where a third-party provider delivers hardware and software tools over the internet, including infrastructure, operating systems, and middleware. The company then deploys and manages its own applications and data on this platform, aligning perfectly with the specified requirements.

A private cloud refers to a cloud environment dedicated to a single organization. While it can meet the requirements, 'PaaS' is the specific service model that describes the shared responsibility outlined, regardless of whether it's a private or public cloud deployment.