Explanation: The question describes the fundamental definition of the coulomb. An ampere is defined as the flow of one coulomb of electrical charge per second past a given point. Therefore, if a current of one ampere is flowing for one second, the amount of charge that has passed is one coulomb. This relationship is expressed by the formula Q = I * t, where Q is charge in coulombs, I is current in amperes, and t is time in seconds. Joule (B) is a unit of energy or work. Watt (C) is a unit of power, representing the rate at which energy is transferred or consumed (Joules per second). Neither of these measures electrical charge.