Which of the following is NOT a characteristic of Software as a Service (SaaS)?

B is the correct choice because Software as a Service (SaaS) is designed to be accessible via the cloud, which inherently eliminates the need for significant upfront hardware investments. Instead of requiring users to buy and maintain servers or other hardware, SaaS allows them to access software applications over the internet, typically on a subscription basis.

In SaaS models, users pay for what they use, usually through a monthly or annual subscription, which can often include features like automatic updates and scalability, allowing businesses to adjust their usage as needed without the constraints of physical hardware. Thus, the essence of SaaS is centered around minimizing capital expenditure on hardware while providing flexible, scalable software solutions hosted in the cloud. The other choices describe characteristics that are indeed part of SaaS, such as being cloud-based, enabling subscription access, and allowing easy scalability.