An open wire will measure?

In the context of electrical measurements, an open wire refers to a wire that is not conducting current due to a break or disconnection in the circuit. When measuring resistance across an open wire with a multimeter, it essentially acts like an infinite gap in the circuit, which leads the meter to indicate the maximum resistance possible. This happens because the multimeter will not find a complete circuit to measure current flowing through; instead, it will register as if no conductive path exists.

Therefore, the correct response is that an open wire will measure maximum resistance. The measurement can effectively be seen as "infinity" since there's no way for current to pass through an open circuit. This is a fundamental principle in electrical engineering and is crucial for diagnosing circuit issues involving breaks or disconnections in wiring.