Which of the following reactions is not an example of a nucleophilic addition-elimination reaction?

$(CH_3)_3CCHO$ does not undergo aldol condensation due to

Trichloroacetaldehyde was subjected to Cannizzaro's reaction by using $NaOH$. The mixture of the products contains sodium trichloroacetate and another compound. The other compound is:

$A$ compound $A$ with molecular formula $C_{10}H_{13}Cl$ gives a white precipitate on adding silver nitrate solution. $A$ on reacting with alcoholic $KOH$ gives compound $B$ as the main product. $B$ on ozonolysis gives $C$ and $D$. $C$ gives Cannizzaro reaction but not aldol condensation. $D$ gives aldol condensation but not Cannizzaro reaction. $A$ is:

Which of the following compounds is highly reactive towards $HCN$?

$PhMgBr$ [Excess] + $CH_3COCl \xrightarrow{H_3O^+}$
The final product of the above reaction is: