For connecting to a plotter or a graphics-capable printer, a computer typically requires graphics capability (a graphics board/adapter) to generate and drive the appropriate raster/vector signals and device drivers.

Introduction / Context:
Plotters and many printers rely on graphics pipelines to render images, engineering drawings, and complex layouts. While the physical interface can be serial, parallel, USB, or network, the host must still create graphics output. A graphics board (or integrated graphics adapter) provides the hardware acceleration and driver stack needed to generate raster/vector data effectively.

Given Data / Assumptions:

• The device is a plotter or graphics-capable printer.
• The host computer must render images or vector paths.
• We assume standard desktop/workstation scenarios.

Concept / Approach:
Graphics capability includes hardware and drivers that translate drawing commands into bitmaps or vector instructions suitable for device-specific languages (e.g., HP-GL/2, PostScript). A mere cable does not provide rendering; a monitor is an output device, not a requirement for printing; and a general-purpose co-processor does not specifically enable graphics rendering. Hence, the enabling capability is the graphics board (or equivalent integrated GPU) plus drivers.

Step-by-Step Solution:
Identify what enables rendering: graphics hardware and drivers.Differentiate from passive accessories (cable, monitor).Note that co-processors are not specialized for graphics output.Select “A graphics board.”

Verification / Alternative check:
Workstations used for CAD/CAM pair certified GPU drivers with plotters/printers to ensure accurate vector/raster rendering and color management.

Why Other Options Are Wrong:
Graphics cable: necessary for connection but does not provide capability.RGB monitor: a display device, irrelevant to printer/plotter rendering.Co-processor: not specifically tied to plotter/printer graphics generation.None of the above: incorrect because a graphics board is appropriate.

Common Pitfalls:
Confusing physical connectivity with rendering capability; overlooking driver compatibility and print language support, which can cause incorrect scaling or missing vectors.

Final Answer:
A graphics board