Electric power is defined as the
A. Product of potential and charge flowing through it.
B. Product of potential difference applied across the circuit and current flowing through it.
C. Product of current and energy.
D. None

Hint: In order to solve this question, firstly we will understand the concept of electric power i.e. $P = \dfrac{{VQ}}{t} = VI$. Then we will compare all the given options to find the accurate definition of electric power.

Complete step-by-step answer:

Electric power is defined as the product of potential difference applied across the circuit and the current flowing through it. It may be defined as the rate, per unit time, at which electrical energy is transferred by an electric circuit. The SI unit of electric power is watt or one joule per second.
The main source of electric power is usually electric generators, but can also be produced by sources such as electric batteries.Mostly electric power is usually supplied to businesses and homes (as household mains electricity) through an electric power grid by the electric power industry.
In watts the electric power is bring out by an electric current I which consists of a charge of Q coulombs every t seconds passing through an electric potential (voltage) difference of V is-

$P = \dfrac{{VQ}}{t} = VI$
Where

P is the work done per unit time
Q is electric charge in coulombs
t is time in seconds
I is electric current in amperes
V is electric potential or voltage in volts.

It can also be transformed to other forms of energy when the electric charges move through an electric potential (voltage) difference, which occurs in electrical components in electric circuits.
Therefore, we conclude that Electric power is defined as the product of potential difference applied across the circuit and the current flowing through it.

Hence, option B is correct.

Note: While solving this question, we must know that Electric power is widely used in industrial, commercial and consumer applications. Electric energy is used directly in processes such as extraction of aluminum from its ores.