To accurately determine the exact point location of a discontinuity, the test system should include:

The correct answer, which highlights the importance of the probe coil, is grounded in its fundamental role in electromagnetic testing methods. A probe coil is essential for determining the exact location of a discontinuity because it is designed to generate and detect the electromagnetic fields generated by the presence of flaws or discontinuities within the material being tested.

In the context of eddy current testing, for example, the probe coil interacts with conductive materials, and its design influences the sensitivity and spatial resolution of the test. When a discontinuity such as a crack or void is present, the probe coil detects changes in the impedance of the coil caused by variations in the electromagnetic fields. This allows for precise measurements not only of the presence of the discontinuity but also of its exact location.

The other options, while useful in specific contexts, do not directly contribute to pinpointing the location of deficiencies in the same focused manner as the probe coil. A phase shifter is primarily used to adjust the phase of the signal in testing but does not localize discontinuities. An attenuator serves to reduce signal strength but does not aid in confirming or identifying the presence of a defect. A penetrameter is a device used to evaluate the sensitivity of testing techniques and is not specifically meant for locating