Which measurement tool is crucial for troubleshooting electrical circuits?

The multi-meter is essential for troubleshooting electrical circuits because it can measure various electrical parameters such as voltage, current, and resistance, allowing users to diagnose issues within the circuit effectively. By using a multi-meter, one can evaluate whether components are functioning correctly or if there are breaks or shorts within the circuit. This ability to analyze the behavior of electrical circuits makes the multi-meter an invaluable tool for both troubleshooting and ensuring circuits operate as intended.

In contrast, while a caliper is useful for measuring dimensions very precisely, it does not have the capability to evaluate electrical specifications. An oscilloscope, though also a valuable tool in analyzing electrical signals, is more specialized for observing waveform shapes and is typically used for more advanced diagnostics rather than basic troubleshooting. A torque wrench is designed for applying a specific torque to fasteners and has no application in the analysis or troubleshooting of electrical circuits. Thus, the multi-meter stands out as the most relevant tool in this context.