c
\(CH{\left( {CN} \right)_3} \rightleftharpoons \mathop C\limits^ - {\left( {CN} \right)_3} + {H^ + }\) Negative charge of the conjugate base \(\mathop C\limits^ - {\left( {CN} \right)_3}\) in extensively delocalized through the \(C \equiv N\) group.