`KMnO_(4)` react with oxalic acid according to the equation, `2MnO_(4)^(-)+5C_(2)O_(4)^(2-)+16H^(+) rarr 2Mn^(2+)+ 10 CO_(2)+8H_(2)O`, here `20 ml` of `0.1 M KMnO_(4)` is equivalemt to
A. (a)`20 "ml of" 0.5 M H_(2)C_(2)O_(4)`
B. (b)`50 "ml of" 0.1 M H_(2)C_(2)O_(4)`
C. (c )`50 " ml of" 0.5 M H_(2)C_(2)O_(4)`
D. (d)`20 "ml of" 0.1 M H_(2)C_(2)O_(4)`