[amp_mcq option1=”Protons only” option2=”Electrons, protons, and ions” option3=”Electrons, ions, and neutrons” option4=”Electrons, protons, and neutrons E. None of the above” correct=”option4″]
The correct answer is D. Electrons, protons, and neutrons.
Protons and neutrons are located in the nucleus of the atom, while electrons orbit the nucleus. The number of protons in an atom determines its chemical element, while the number of neutrons determines its isotope. The number of electrons in an atom is equal to the number of protons, so the atom is electrically neutral.
Option A is incorrect because protons are not the only particles in an atom. Neutrons and electrons are also present.
Option B is incorrect because ions are not fundamental particles. They are formed when atoms or molecules gain or lose electrons.
Option C is incorrect because neutrons are not present in ions.
Option E is incorrect because electrons, protons, and neutrons are all present in atoms.