Correct option is C
In the process of lapping, the term “charging” refers to the operation of embedding abrasive particles into the surface of the lap tool. The lap is usually made of a soft material such as cast iron, copper, or lead, which can easily hold abrasive particles like silicon carbide or diamond. During charging, these abrasive grains are pressed into the lap surface so that they act as cutting edges during the finishing process.
This is a crucial step because the effectiveness of lapping depends on how well the abrasive particles are retained on the lap. Once charged, the lap can produce extremely smooth surfaces, high dimensional accuracy, and fine tolerances, which are essential in precision engineering applications such as gauges, engine components, and optical parts.
