The rapid change of `pH` near the stoichiometric point of an acid-base titration is the basic of indicator detection. `pH` of the solution is related to the ratio of the concentration of conjugate acid `(Hin)` and base `(In^(-))` forms of the indicator by the expression
A. `"log""[Hln]"/([In^-])=pK_"In"-pH`
B. `"log""[Hln]"/([In^-])=pH-pK_"In"`
C. `"log" ([In^-])/"[Hln]"=pH-pK_"In"`
D. `"log" ([In^-])/"[Hln]"=pK_"In"-pH`
