(a) The aim of the reaction is to attach a acid group (-COOH group) to an aromatic system.(b)The aim of the reaction is to attach a alcohlic group (-OH group) to an aromatic system.(c)The aim of the reaction is to attach a formyl group (-CHO group) to an aromatic system.(d) The aim of the reaction is to attach a formyl group (-CHO group) to an aliphatic system.