A electron is released from rest in a uniform electric field oriented from left to right. What happens to the electric potential energy of the proton-electric field system? A. IncreaseB. DecreaseC. Remains the same

When electron is released in an electric field, it will move in the direction opposite to the direction of field. In this process, force is applied by the field and work is done by the field. So its electric potential energy will be decreased because, its energy is converted into kinetic energy of the electron.