Which of the following is a key term associated with electric rates?

The key term associated with electric rates is kilowatt-hour (kWh). This unit is fundamental in measuring electrical energy consumption. It indicates the amount of energy used when a device with a power rating of one kilowatt operates for one hour. Electric rates are commonly expressed in terms of cost per kWh, making this unit essential for consumers to understand how their usage translates into their bills.

The other options relate to different fields: pH measures the acidity or alkalinity of a solution, BTU (British Thermal Unit) is used to measure energy in the heating and cooling industries, and psi (pounds per square inch) is a unit of pressure. While all these terms are valuable in their respective contexts, kWh is specifically relevant to electricity and its pricing structure.