\[\begin {array} {1 1} (a)\;CH_3CHO,(CH_3)_2CO,NaOH \\ (b)\;CH_3CHO,CH_3CHO,NaCl \\ (c)\;(CH_3)_2CO,(CH_3)_2CO,HCl \\ (d)\;CH_3CHO,CH_3CHO,NaOH \end {array}\]
