To determine the diameter of a small hole, which of the listed tools must be used with inside calipers to get an accurate reading?

Correct Answer: Option B — Micrometer

To determine the diameter of a small hole, inside calipers are used to transfer the internal dimension to a micrometer. The micrometer then provides the precise numerical reading. This two-step process is essential for verifying internal clearances in bushings and cylinders to ensure compliance with machinery tolerances.