Which tool is used to trace the path of cables and identify which wall outlet is connected to which port?

• A. Time-domain reflectometer
• B. Multimeter
• C. OTDR
• D. Toner and probe

Answer: (D)

Tracing cables and matching endpoints relies on sending a signal down a conductor and listening for it at the other end. A toner and probe does exactly that: the tone generator injects a distinctive audio signal into the cable, and the handheld probe detects that tone as you trace the route, letting you identify which wall outlet connects to a given port at a switch or patch panel. This lets you map endpoints without opening walls or testing each pair visually.

By comparison, a time-domain reflectometer (TDR) or its fiber counterpart (OTDR) sends a pulse and looks for reflections to locate faults or impedance changes along a line, which is about diagnosing where a break or flaw occurs rather than mapping endpoints. A multimeter checks electrical values like voltage, resistance, or continuity but doesn’t reveal how outlets and ports are connected or trace a cable’s path. So toner and probe is the best tool for this specific task.