Final answer:
The top-down troubleshooting approach is the most suitable for diagnosing a simple network problem caused by software, starting from the highest level of the system's functionality and working downward to isolate the issue.
Step-by-step explanation:
When troubleshooting a simple network problem that is suspected to be caused by software, the most appropriate approach to use is often a top-down method. This method starts at the highest level of the system's functionality and works downward. You begin by examining the application layer, ensuring that software configurations and settings are correct, then move on to network configurations and eventually to the individual network components. This approach allows for systematic isolation of the issue, often making it easier to identify the exact nature of a software problem within a network environment.