'A' and 'B' respectively are: A →[ (2) Zn - H_2 O ] (1) O_3 Ethane-1,2-dicarbaldehyde + Glyoxal/Oxaldehyde; B →[ (2) Zn - H_2 O ] (1) O_3 5-oxohexanal

'A' and 'B' respectively are : $$\begin{aligned} & \text { A } \xrightarrow[\text { (2) } \mathrm{Zn}-\mathrm{H}_2 \mathrm{O}]{\text { (1) } \mathrm{O}_3} \text { Ethane-1,2-dicarbaldehyde + Glyoxal/Oxaldehyde } \\ & \text { B } \xrightarrow[\text { (2) } \mathrm{Zn}-\mathrm{H}_2 \mathrm{O}]{\text { (1) } \mathrm{O}_3} \text { 5-oxohexanal } \end{aligned} $$