Aniline is treated with $NaNO_2 + HCl$ at low temperature to form:

Which of the following reactions can produce aniline as the main product?

In the following sequence of reactions,the compound $A$ is:
$A$ $\xrightarrow{\text{Reduction}} B$ $\xrightarrow{HNO_2} CH_3CH_2OH$

An organic compound $A$ on reaction with $NH_{3}$ followed by heating gives compound $B$. Which on further strong heating gives compound $C$ $(C_{8}H_{5}NO_{2})$. Compound $C$ on sequential reaction with ethanolic $KOH$,alkyl chloride and hydrolysis with alkali gives a primary amine. The compound $A$ is.

Which one of the following compounds gives a secondary amine on reduction?

The diazonium salts are the reaction products in the presence of excess of mineral acid with nitrous acid and: