Which of the following is a lever that can be moved in several directions to control the movement of an image on a computer monitor or similar display screen ?

The correct answer is A, Joystick. A joystick is an input device with a stick fixed in a base that can be tilted in several directions, and the movement of the stick moves an image or a pointer on the screen in the same direction. It was first built for aircraft controls, and today it is used for computer games, flight simulators, wheelchairs and cranes. Most joysticks also carry buttons and a trigger, and the base sends the direction and the amount of tilt to the computer, so it is an analog pointing device like the mouse, the trackball and the light pen. B is wrong because an Optical Mark Reader only reads pencil marks on answer sheets and forms. C is wrong because a Visual Display Unit is the monitor, which is an output device and controls nothing. D is wrong because MIDI devices such as electronic keyboards carry music data between instruments and a computer. Exam tip: joystick, mouse, trackball, light pen and touch screen are pointing input devices; the monitor and printer are output devices.