Final answer:
It is true that all drivers, including non-PnP devices, are shown in Device Manager, with non-PnP devices typically listed under 'Legacy' hardware.
Step-by-step explanation:
The statement that all drivers, including non-PnP (Plug and Play) devices, are represented in the Device Manager as viewable nodes is true. Device Manager in Windows operating systems indeed shows all devices that are currently installed on the system, which includes both PnP and non-PnP devices. Non-PnP devices, which may require manual installation and configuration due to their inability to be recognized automatically by the operating system, are typically listed under the 'Legacy' hardware section in Device Manager, whereas PnP devices are generally detected and configured automatically.