Which side of the battery has the higher electric potential energy?

The correct choice is that the right side of the battery has the higher electric potential energy. In a typical setup, batteries have two terminals: positive and negative. The potential energy in a battery is higher at the positive terminal compared to the negative terminal due to the chemical reactions within the battery that create a voltage difference.

In a conventional battery, the right side is often associated with the positive terminal, where electric potential is greater. This difference in electric potential energy is what drives the flow of electrons from the negative terminal to the positive terminal when the battery is connected in a circuit. More electric potential energy at the right side means it will have the capacity to do more work when the circuit is completed.

The other choices do not fully capture the principles of how batteries function or assume a scenario where the electric potential is the same at both terminals, which is contrary to the fundamental operation of standard batteries. Hence, the logic behind determining which side of a battery has higher electric potential energy hinges on recognizing the role of the positive terminal in facilitating electric current flow.