Cloud Computing

Correct Answer: PaaS

PaaS (Platform as a Service) is the correct answer. This is because PaaS delivers a platform to users, allowing them to develop, run, and manage applications without the complexity of building and maintaining the infrastructure typically associated with app development and launch. Thus, PaaS meets the small business's need to focus on developing their applications and not on managing the underlying infrastructure. IaaS (Infrastructure as a Service) is not the best fit as it does provide access to the underlying infrastructure but still requires the user to manage it. SaaS (Software as a Service) doesn’t fit because it is software delivery model where the service provider hosts the application and users can access it over the internet; it doesn’t provide an environment for development. CaaS (Container as a Service) doesn't fit the description either as it specifically involves container-based virtualization for application deployment and may not necessarily free the user from infrastructure management.

Correct Answer: IaaS

The correct answer is IaaS (Infrastructure as a Service). This is because IaaS provides the best solution for running out of storage on a web server, as it provides raw storage capacity, network, and virtual server resources. This allows the company to immediately scale up storage capacity on demand, without having to invest in physical storage infrastructure. On the other hand, SaaS (Software as a Service) is more about using software applications over the internet on a subscription basis and is not specifically designed to cope with storage scalability. PaaS (Platform as a Service) provides a platform for software development and deployment, and it's not the best fit for dealing with storage issues. And CaaS (Container as a Service) is more for managing and deploying software containers, not for scalable storage.

Correct Answer: SaaS

Software as a Service (SaaS) is the best choice for this company. SaaS migrates the on-premises Exchange server to a cloud-hosted solution, such as Microsoft's Office 365, where the software is delivered over the internet and managed by a third-party vendor. The company doesn't have to worry about managing the server or infrastructure which significantly reduces their workload. In contrast, Infrastructure as a Service (IaaS) is when the company still has to manage some parts of the infrastructure, such as the middleware, runtime, applications, and data. Platform as a Service (PaaS) is a cloud computing model in which a third-party provider delivers hardware and software tools, but the company would still need to manage the applications and data. Containers as a Service (CaaS) is a cloud service model that allows developers to manage and deploy containers, orchestration, and computational resources. This would not be suitable for reducing the company's server management burden as it still requires the company to manage some parts of the infrastructure.