Using your periodic table identify the radioactive isotope;

It should be Carbon (C), Potassium (K), Cadmium (Cd), and Bismuth (Bi) 

There is one s orbital, and there are three p orbitals, five d orbitals, and seven f orbitals. thus, the answer is b. do not confuse the number of orbitals in a subshell with the number of electrons the subshell can hold. each orbital can hold two electrons, so the capacity of an nf subshell is 14 electrons.