Ohm (Ω) describes the amount of resistance electricity encounters. It is one of the base units of the International System of Units (SI), and is defined as the amount of resistance that a conductor has when a force of one volt is applied across it. Ohms are used to measure the electrical resistance of a circuit, and can be used to determine the power of a circuit or the amount of current flowing through it.

A Standby Generator System is a combination of an electrical generator and a mechanical engine mounted together to form a single piece of equipment. The generator provides power to essential appliances and equipment in the event of a power outage. Standby Generator Systems are usually powered by gasoline, diesel, natural gas, or propane, and they are designed to be able to be activated quickly in the event of an emergency.

AC can be transformed from a low voltage to a high voltage and back again with a transformer, while DC cannot. This makes it easier to distribute AC electricity over long distances and is why it is used more widely than DC electricity. A and B are also true, as wires carrying AC can be bare and don't need to be totally insulated. Wires have less resistance when carrying AC electricity, which is why it is more efficient than DC.