Which of the following is used for precise internal diameter measurements?

The correct choice for precise internal diameter measurements is the telescoping gauge. This tool is specifically designed to measure the internal dimensions of holes, tubes, or any other cylindrical object. When using a telescoping gauge, the user inserts the gauge into the hole and expands it to fit firmly against the internal surface. Once in place, the gauge can then be removed and measured with a micrometer or caliper for an accurate reading of the diameter.

In contrast, a feeler gauge is used primarily for measuring gap widths and cannot effectively measure internal diameters. A micrometer is an excellent tool for precise measurements, but it is typically used for measuring external dimensions or thicknesses, not internal diameters directly. A caliper is versatile and can measure both internal and external dimensions, but it is generally less precise than a telescoping gauge for narrow or deep internal measurements. Therefore, the telescoping gauge is the most appropriate tool for achieving highly accurate internal diameter measurements.