With Function as a Service (FaaS), you may not be able to access the computing system the function is operating on. So, that is not the best answer. With Software as a Service, (SaaS) again, you may only have access to the application. So, that is another incorrect answer. With Platform as a Service (PaaS), you have additional access to the coding environment. But that is not what we are looking for. Finally, Infrastructure as a service (IaaS) environments provide analysts with access to the operating system, allowing deeper forensic analysis than other cloud platforms that operate higher in the stack.