# A radioactive nucleus (initial mass number A and atomic number Z) emits 3 $\alpha$ particles and 2 positrons. The ratio of number of neutrons to that of protons in the final nucleus will be
( A ) $\large\frac{A-Z-12}{Z-4}$
( B ) $\large\frac{A-Z-8}{Z-4}$
( C ) $\large\frac{A-Z-4}{Z-8}$
( D ) $\large\frac{A-Z-4}{Z-2}$