Final answer:
Electric companies use a kilowatt-hour meter to measure the household energy usage in kilowatt-hours, which reflects the energy used by devices with a power rate of one kilowatt over an hour.
Step-by-step explanation:
Electric companies use a device to measure the energy consumption of a household. Electric companies use a kilowatt-hour meter to measure the household energy usage in kilowatt-hours, which reflects the energy used by devices with a power rate of one kilowatt over an hour.
This device is known as a kilowatt-hour meter, which allows them to determine how many kilowatt-hours (kWh) of energy are used. A kilowatt-hour is the amount of energy used by a device with a power consumption rate of one kilowatt over a period of one hour.
The kilowatt-hour is the preferred unit for electric utility companies because it corresponds to the typical range of electrical power consumption for households. The correct answer to the question is A. kilowatt-hour meter.