The correct answer is B. 6
Explanation:
Each atom of an element is composed of a certain amount of protons, electrons, and neutrons. In the case of electrons, the number of electrons is the same as the protons in the case of atoms that are neutrally charged. Additionally, the atomic number of an atom indicated the number of electrons in it and the atomic mass the number of electrons and protons together.
This means by knowing the number of protons which in this case is 6 (Atomic number) and the atomic mass which is 12 it is possible to determine the number of electrons. Either because the number of electrons is the same that the number of atoms which means is 6 or the atomic mass minus the protons are the number of electrons, which is also 6 (12-6 = 6).
