An atom of boron has an atomic number of 5 and an atomic mass of 11. The atom contains:. . A. 5 protons, 6 electrons, and 5 neutrons.. . B. 11 protons, 11 electrons, and 5 neutrons.. . C. 5 protons, 5 electrons, and 6 neutrons.. . D. 11 protons, 6 electrons, and 6 neutrons.