A ___________ is usually a display device used to produce a paper record of analog wave form.

Graphic pen recorder
Electron microscope
X-Y recorder
Oscilloscope

The correct answer is: A. Graphic pen recorder

A graphic pen recorder is a device that produces a paper record of an analog waveform. It is usually used to measure and record electrical signals, such as those produced by a heart monitor or an oscilloscope. The pen recorder consists of a moving pen that traces the waveform on a piece of paper. The paper is moved past the pen at a constant speed, and the pen is controlled by an electronic circuit that converts the analog signal into a series of electrical pulses. The pulses cause the pen to move up and down, creating a record of the waveform on the paper.

The other options are incorrect because:

  • An electron microscope is a device that uses a beam of electrons to create an image of a very small object.
  • An X-Y recorder is a device that plots the relationship between two variables, such as voltage and time.
  • An oscilloscope is a device that displays a visual representation of an electrical signal.