Which two devices are the most common input devices for computers?

The keyboard and mouse are the most common input devices for computers because they serve as primary means for users to interact with and control the computer environment.

The keyboard allows users to input text and commands through various keys, providing an efficient way to enter data, execute commands, and navigate applications. It is an essential tool for tasks that require a significant amount of typing, such as word processing, programming, and data entry.

The mouse complements the keyboard by enabling users to interact with graphical user interfaces (GUIs). It allows for precise cursor control, making it easier to select, drag, and drop items on the screen, as well as navigate through menus and applications. The combination of both devices provides a versatile and intuitive method for users to communicate with their computer.

While other options include different combinations of devices, they do not feature the standard pairing of input devices as effectively as the keyboard and mouse. The monitor, printer, and optical scanner, for example, serve different roles such as displaying output or scanning, rather than facilitating direct input.