Nitrobenzene on treatment with zinc dust and aqueous ammonium chloride gives

The order of basicity of amines in the gaseous state is

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

Identify the products $y$ and $x$ in the following reaction sequence:
$C_6H_5CONH_2 \xrightarrow{NaOBr} y$
$C_6H_5CONH_2 \xrightarrow[(ii) H_3O^+]{(i) C_6H_5SO_2Cl / py, \Delta} x$

Compound $A$ is converted to $B$ on reaction with $CHCl_3$ and $KOH$. The compound $B$ is toxic and can be decomposed by $C$. $A, B$ and $C$ respectively are:

In the reaction sequence $A$ $\xrightarrow{Sn/HCl} B$ $\xrightarrow{HNO_2, 0^{\circ}C} C$ $\xrightarrow{C_2H_5OH} C_6H_6$,identify the functional groups present in $A, B,$ and $C$.