In the chemical reaction $CH_3Cl$ $\xrightarrow{AgCN} (A)$ $\xrightarrow{H_2/Pd} (B)$,what is the structure of $(B)$?

$(A)$ $\xrightarrow[(1) \text{ excess } CH_3I/K_2CO_3, (2) \text{ } Ag_2O/H_2O, (3) \text{ } \Delta]{} (B)$ $\xrightarrow[(i) \text{ excess } CH_3I/K_2CO_3, (ii) \text{ } Ag_2O, (iii) \text{ } \Delta]{} H_2C=CH-CH(CH_3)-CH=CH_2$. Identify $(A)$.

Consider the following four compounds $I, II, III,$ and $IV$.
Choose the correct statement$(s)$.
$(A)$ The order of basicity is $II > I > III > IV$.
$(B)$ The magnitude of $pK_b$ difference between $I$ and $II$ is more than that between $III$ and $IV$.
$(C)$ Resonance effect is more in $III$ than in $IV$.
$(D)$ Steric effect makes compound $IV$ more basic than $III$.

Among the isomeric amines,select the one with the lowest boiling point.

$R-NH-CHO \xrightarrow[\text{pyridine}]{POCl_3} \text{ product}$
In the given reaction,what will be the product?

Reduction of nitrobenzene with $Zn$ and alcoholic $KOH$ solution results in the formation of the following compound: