Which of the following describes a characteristic of knob-and-tube wiring?

Knob-and-tube wiring is a historical type of electrical wiring that predominantly consists of only two wires: a hot wire and a neutral wire. This wiring system dates back to the late 1800s and early 1900s and was widely used until the 1940s.

The hot wire carries electrical current to fixtures and outlets, while the neutral wire provides a return path for the current. Notably, knob-and-tube wiring does not include a ground wire, which is a significant difference from modern wiring systems that generally incorporate a ground wire for safety reasons.

Understanding that knob-and-tube wiring lacks advanced safety features, such as separate ground wires and complex breaker systems, is crucial when evaluating older electrical systems. The simplicity of having only two wires is a defining characteristic of knob-and-tube wiring that distinguishes it from more contemporary wiring methods that prioritize user safety and code compliance.