The product of the reaction $image \xrightarrow[{HCl}]{{NaNO_2}} (A)$ is:

Identify $Y$ in the following reaction sequence:
$C_6H_5NH_2$ $\xrightarrow[5^{\circ}C]{NaNO_2 + HCl} X$ $\xrightarrow{H_3PO_2 / H_2O} Y$

The reagent used for the protection of the amino group during the nitration of aniline is:

Identify the major products $X$,$Y$,and $Z$ in the following sequence of transformations:

The major product in the following reaction is:

$A$ compound $X$ on treatment with $Br_2/NaOH$ provided $C_3H_9N$,which gives a positive carbylamine test. Compound $X$ is