The end product $C$ of the following reaction is

$$\mathrm{C}_2 \mathrm{H}_5 \mathrm{NH}_2 \xrightarrow{\mathrm{HNO}_2} A \xrightarrow{\mathrm{PCl}_5} B \xrightarrow[\text { Alcohol }]{\mathrm{NH}_3} C$$

Which of the following amines is most basic in nature in aqueous phase?

Which of the following reaction of diazonium salt involves retention of diazonium group?

Identify compound '$$B$$' in following series of reactions?

$$\text { Acetonitrile } \xrightarrow{\mathrm{Na} / \text { alcohol }} A \xrightarrow{\mathrm{NaNO}_2 / \text { dil. } \mathrm{HCl}} B$$