The equivalent conductance of `1 M` benzoic acid is `12.8 ohm^(-1) cm^(2)`. If the conductance of benzoate ion and `H^(+)` ion are `12` and `288.42 ohm^(-1) cm^(2)` respectively. Its degree of dissociation is :
A. `39 %`
B. `3.9 %`
C. `0.35 %`
D. `0.039 %`