Correct option is D
Lapping is an
ultra-precision finishing process used to achieve
very high accuracy and smooth surface finishes. It is commonly used for
optical components, gauges, bearings, and precision machine parts.
The
International Tolerance (IT) grade system defines the
precision levels of machining processes. Lapping can achieve an
extremely fine tolerance range, typically
IT1 or IT2. The best accuracy is
IT1, making it the correct answer.
