The isotope deuterium of hydrogen has I. No neutrons and one proton II. One neutrons and two protons III. One electron and two neutron IV. One proton and one neutron
Tritium has one proton, one electron, and two neutrons. So, the isotope deuterium of hydrogen has one proton and one neutron. Therefore, option (D) one proton and one neutron is the correct answer.
