Which of the following is NOT an output device?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. Bar code reader.
A barcode reader is NOT an output device. It is an input device because it captures and sends data to a computer. Output devices are used to display, project, or physically reproduce the results of computer processing, like monitors, printers, and speakers. In contrast, a barcode reader scans printed barcodes and converts them into digital data that the computer can process. It does not produce information for the user to view or use directly, but rather sends information into the system for further action. Thus, barcode reader is the correct answer as it serves as an input, not output, device.