Which unit is used to measure capacitance?

Capacitance is a measure of a capacitor's ability to store an electric charge. The unit used to measure capacitance is the farad, which defines how much charge a capacitor can hold per volt of electric potential. One farad is equivalent to one coulomb of charge stored per volt. This unit reflects the relationship between charge (in coulombs), voltage (in volts), and capacitance, which is fundamental to understanding electrical circuits.

Other units mentioned in the question serve different purposes. Meters measure length, volts measure electrical potential difference, and ampere-hours quantify electrical charge over time, none of which define the property of capacitance directly. Thus, the farad is the appropriate and correct unit for expressing capacitance in electrical and electronic applications.