Option 1 -> Volt is the unit of electric potential difference, not charge.
Option 2 -> Watt is the unit of power (rate of energy consumption), not charge.
Option 3 -> Ampere is the unit of electric current (rate of charge flow), not charge itself.
Option 4 -> Kilowatt hour is the commercial unit used for electrical energy consumption in billing.
Hence, Kilowatt hour (kWh) -> While the SI unit of charge is Coulomb, in commercial practice, electricity companies bill consumers based on energy consumed, measured in kilowatt hours (1 kWh = 1000 watts used for 1 hour). This is the standard unit on electricity bills worldwide -> correct