In the following sequence of reactions,the final product $D$ is:

In the following conversion,
$C_6H_5CN$ $\xrightarrow[(ii) H_3O^+]{(i) MeMgBr} X$ $\xrightarrow[H_3O^+]{NaOH/I_2} Y$
the major products $X$ and $Y$,respectively are

The product $(A)$ is:

Which of the following undergoes haloform reaction?
$ (i) \ CH_3CH_2COCH_2Cl $
$ (ii) \ C_6H_5COCH_3 $
$ (iii) \ C_6H_5COCHCl_2 $
$ (iv) \ CH_3CH_2COCCl_3 $

Identify $A$ and $B$ from the following reactions:
$(I)$ $CH_3-CH=CH-CH_3 \xrightarrow{\text{(i) } O_3}{\text{(ii) } Zn-H_2O} 2X$
$(II)$ $2X$ $\xrightarrow[2. \Delta]{1. NaOH \text{ (dil.)}} Z$ $\xrightarrow[\text{(ii) } Zn-H_2O]{\text{(i) } O_3} A + B$

Given below are two statements $:$
Statement $(I) :$ Vanillin,with the structure shown below,will react with $NaOH$ and also with Tollen's reagent.
Statement $(II) :$ Vanillin will undergo self-aldol condensation very easily.
In the light of the above statements,choose the most appropriate answer from the options given below $:$