Which of the following is a characteristic of Software as a Service (SaaS)?

The characteristic that applications are hosted on a vendor's infrastructure and accessed over the internet captures the essence of Software as a Service (SaaS). In a SaaS model, software applications are centrally hosted on the provider's servers rather than on the user's local machine. This allows users to access the software from anywhere with an internet connection, making it highly convenient and flexible.

The vendor takes care of all infrastructure management, including maintenance, upgrading, and security, enabling users to focus solely on using the applications rather than worrying about the underlying technical details. This setup is particularly beneficial for organizations looking to minimize IT overhead and streamline operations, as they do not need to invest in on-premises hardware or deal with the complexities of installation and updates.

In contrast, the other options do not accurately reflect the nature of SaaS. For example, users being responsible for managing the underlying infrastructure does not align with the SaaS model, where that responsibility lies with the service provider. Similarly, the requirement for users to install software locally contradicts the fundamental way SaaS applications are accessed. Lastly, while SaaS can include software development tools, its applicability is not limited to that category alone; it spans a wide range of applications across various domains.