For a nucleus ${ }_Z^A X$ having mass number $A$ and atomic number $Z$
A. The surface energy per nucleon $\left(\mathrm{b}_{\mathrm{s}}\right)=\mathrm{a}_1 \mathrm{~A}^{2 / 3}$
B. The Coulomb contribution to the binding energy $b_c=-a_2 \frac{Z(Z-1)}{A^{4 / 3}}$
C. The volume energy $\mathrm{b}_{\mathrm{v}}=\mathrm{a}_3 \mathrm{~A}$
D. Decrease in the binding energy is proportional to surface area.
E. While estimating the surface energy, it is assumed that each nucleon interacts with 12 nucleons, (a1, $\mathrm{a}_2$ and $\mathrm{a}_3$ are constants)
Choose the most appropriate answer from the options given below: