Explanation: Conductance is the ease with which an electric current flows through a material. It is the reciprocal of resistance. Where resistance measures the opposition to current flow, conductance measures how readily current flows. The unit of resistance is the Ohm. Therefore, the unit of conductance, being the reciprocal of resistance, was historically named the **Mho** (Ohm spelled backward). While Mho is still commonly used and understood in amateur radio contexts, the international standard unit for conductance is now the Siemens. Let's look at the other options: * **A) Ohm:** This is the unit of resistance, which is the opposite of conductance. * **C) Henry:** This is the unit of inductance, a measure of an inductor's ability to store energy in a magnetic field. * **D) Ampere:** This is the unit of electric current, a measure of the flow rate of electric charge.