A printer's output is producing solid black sheets without distinct lettering.

The correct answer is A. Imaging drum.

An imaging drum is a part of a laser printer that transfers the toner to the paper. The imaging drum is coated with a photosensitive material that reacts to light and creates an electrostatic charge. The charge attracts the toner particles from the cartridge and forms an image on the drum. The image is then transferred to the paper by heat and pressure from the fuser assembly.

If the imaging drum is defective or damaged, it can cause various printing problems, such as solid black pages, blank pages, streaks, spots, or faded prints. A solid black page can occur when the imaging drum is unable to create a charge pattern on its surface, and instead attracts all the toner from the cartridge. This can happen due to a faulty laser unit, a dirty or scratched drum surface, or a worn-out drum.

To fix this issue, the technician should replace the imaging drum with a new one. The imaging drum usually has a limited lifespan and needs to be replaced periodically. The technician should also check the toner cartridge and the fuser assembly for any signs of damage or leakage123