Which statement best explains why the overall charge on an atom is zero?

The positive charge of the neutrons in the nucleus equals the negative charge in the electron cloud.
The positive charge of the protons in the nucleus equals the negative charge in the electron cloud.
The negative charge of the neutrons in the nucleus equals the positive charge in the electron cloud.
The negative charge of the protons in the nucleus equals the positive charge in the electron cloud.

The positive charge of the protons in the nucleus equals the negative charge in the electron cloud is the statement that best explains why the overall charge on an atom is zero.