Which of these is not an input device?

• A. Keyboard
• B. Mouse
• C. Monitor
• D. Scanner

Answer: (C)

Distinguishing input from output devices is what this item tests. An input device sends data to the computer: a keyboard turns keystrokes into signals, a mouse translates movement and clicks into data, and a scanner converts a physical document into digital form. A monitor, however, is used to display data from the computer. It receives digital signals and renders them as images and text on the screen rather than sending information back to the computer. Therefore, this item identifies the monitor as not an input device. Note that some devices can function as both input and output, like touchscreen displays, but the standard classification used here treats the monitor as an output device.