Dipole moment $\mu =S \times d$
$3.36 \times 10^{29}=S \times 2.6 \times 10^{-10}$
$S= \large\frac{3.336 \times 10^{29}}{2.6 \times 10^{-10}}$
$\qquad = 1. 283 \times 10^{-19}$ coulomb
% ionic character $=\large\frac{1.283 \times 10^{-19}}{1.602 \times 10^{-19}} $$ \times 100$
$\qquad= 80.09 \%$
If one unit charge then $S= 1.602 \times 10^{-19} C$
$\mu =1.602 \times 10^{-19} \times 2.6 \times 10^{-10}$
$\qquad= 4.1652 \times 10^{-29}\;Coulomb \;meter$
Hence D is the correct answer.