Which is not an output device?

None of the mentioned devices is an output device, except a digital camera that has a display screen.

Where an output device can be defined as any device that is capable of displaying information (result) in form of hard copy or soft copy.

Scanner, Printer, Monitor

&

Plotter, Printer, Monitor

Keyboard, Mouse, Scanner, Microphone (Audio Input), Digital Cameras, Joysticks, Webcam, Digital Pen, Barcode Reader

keyboard , mouse , scanner .

a device which not give an output

MICR(Magnetic Ink character reader)

A key board is an input device

Scanner = an input device, so it is not an output device.

The hardwares which are proving data to the system or computer are not an output device such like:

Keyboard, Mouse, Joystick, Webcam, etc.

An output device is normally a command deivice. So to differentiate between a input and an output one should understand what an input or an output is. An input is a status device. It is either1 or0 or on or off. An input device creates the on or off status for the oputput device. For instance in logics (binary systems)1+1=1,  0+0=0,1+0=0,0+1=0 (And Fuction)

Examples of an input device is a limit switch or a thermal switch or an overload unit, start button/signal or stop button/signal. An output device is a unit that converts electrical energy into kinetic or other forms of energy such as a light bulb, heating element, contactor coil, solenoid coil etc. 

computer monitor which displays an image that is received from the computer. Monitors, printers are two of the most common output devices used with a computer