Match the column

Answer

(A-r,s,t); (B-p,s); (C-q,r); (D-r,s,t)

Explanation

(A) Aldol condensation, (in which carbanion (nucleophile) gives nucleophilic addition and last step is dehydration). (B) G.R. attacks on carbonyl group, followed by internal nucleophilic subsititution
(C) `H_(2)SO_(4)` protonates OH group and changes it into good lenving group to give electrophilic carbon which under goes `ArSE_2` intermolecular reaction for ring closure.
(D) Intra molecular aldol condensation involves carbanion, nucleophilic addition and dehydration.