The correct answer is A. Machine tools.
Machine tools are used to cut, shape, and form metal and other materials. They are used in a variety of industries, including manufacturing, construction, and aerospace. Machine tools can be automated using computer numerical control (CNC) systems. CNC systems control the movement of the machine tool’s cutting tools, allowing them to be operated with precision and accuracy.
B. VDUs, or video display units, are used to display information on a screen. They are commonly used in computers, but they can also be used in other devices, such as televisions and projectors. VDUs are not typically used to automate factory production lines.
C. Plotters are used to create drawings and other graphics. They are typically used in engineering and design applications. Plotters are not typically used to automate factory production lines.
D. None of these is the correct answer.