An organic compound A on reacting with NH3 gives B. on heating B gives C. C in the presence of KOH reacts with Br2 to give CH3CH2NH2..A is

A⟶NH3B⟶ΔC⟶KOH/BrCH3CH2NH2The reaction of C with KOH/Br2 to give amine is called Hofmann bromamide reaction. This reaction is given by acid amides only in whichgroup undergoes rearrangement along with the loss of CO2 molecule. Thus, the compound C must be acid amide with three carbon atoms. Hence, the compound C is Since, all the options shows that A is an acid and it forms acid amide on reaction with NH3. Thus, acid must contain three carbon atoms. Hence, the compound A is CH3CH2COOH. The complete series of reaction can be represented as