`V_(1)` ml of NaOH of molarity X and `V_(2)` ml of `Ba(OH)_(2)` of molarity `(y)/(2)` are mixed together. Mixture is completely neutralized by 100 ml `(0.1)/(2)"M H"_(2)SO_(4)`/. If `(V_(1))/(V_(2))=(1)/(4)` and `(x)/(y)=4`, what fraction of acid is neutralized by `Ba(OH)_(2)`?
A. `0.5`
B. `0.25`
C. `0.33`
D. `0.67`