The molecular formula of a commercial resin used for exchanging ions in water softening is `C_(8)H_(7)SO_(3)Na` (Mol.wt.206). What would be the maximum uptake of `Ca^(2+)` ions by the resin when expressed in mole per gram resin?
A. `(1)/(412)`
B. `(1)/(103)`
C. `(1)/(206)`
D. `(2)/(309)`