Two aliphatic aldehydes $\mathbf{P}$ and $\mathbf{Q}$ react in the presence of aqueous $\mathrm{K}_2 \mathrm{CO}_3$ to give compound $\mathbf{R}$, which upon treatment with HCN provides compound $\mathbf{S}$. On acidification and heating, $\mathbf{S}$ gives the product shown below :
Two aliphatic aldehydes $\mathbf{P}$ and $\mathbf{Q}$ react in the presence of aqueous $\mathrm{K}_2 \mathrm{CO}_3$ to give compound $\mathbf{R}$, which upon treatment with HCN provides compound $\mathbf{S}$. On acidification and heating, $\mathbf{S}$ gives the product shown below :
Match each of the compounds given in Column I with the reaction(s), that they can undergo, given in Column II.
| Column I | Column II | ||
|---|---|---|---|
| (A) |  |
(P) | Nucleophilic substitution |
| (B) |  |
(Q) | Elimination |
| (C) |  |
(R) | Nucleophilic addition |
| (D) |  |
(S) | Esterification with acetic anhydride |
| (T) | Dehydrogenation |
A carbonyl compound P, which gives positive iodoform test, undergoes reaction with MeMgBr followed by dehydration to give an olefin Q. Ozonolysis of Q leads to a dicarbonyl compound R, which undergoes intramolecular aldol reaction to give predominantly S.
The structure of the carbonyl compound P is
