Concept:A neutral atom has no overall charge because its positive and negative charges balance exactly.Explanation:Protons are positively charged, and electrons are negatively charged.Neutrons have no charge and only contribute to the mass of the atom.For an atom to be electrically neutral, the total positive charge must equal the total negative charge.Therefore, the number of protons must equal the number of electrons.Answer:Option D: number of protons is equal to that of electrons.