Final answer:
To switch between open documents, the taskbar is used, showing icons for each open item to facilitate easy navigation.
Step-by-step explanation:
The correct answer is D. Taskbar. The taskbar is a bar located at the bottom of the computer screen in the Windows operating system. It provides quick access to open documents, programs, and functions. By clicking on the icons on the taskbar, you can easily switch between open documents or programs.
You can use the taskbar to move easily from one open document to another. When you have multiple documents or programs open on your computer, the taskbar, which is typically located at the bottom of your desktop screen, shows icons for each of the open items. By clicking on these icons, you can switch between the different documents or applications with ease.