Consider an electrical conductor connected across a potential difference $$V$$. Let $$\Delta q$$ be a small charge moving through it in time $$\Delta t$$. If $$I$$ is the electric current through it,
I. the kinetic energy of the charge increases by $$I V \Delta t$$.
II. the electric potential energy of the charge decreases by $$I V \Delta t$$.
III. the thermal energy of the conductor increases by $$I V \Delta t$$.
Choose the correct option.
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