Which of the following methods is the most convenient method to...

Hofmann bromamide degradation reaction is used for the preparation of primary amines from primary amides. In this reaction, a primary amide is treated with bromine in an aqueous or ethanolic solution of sodium hydroxide.

The general reaction is given by:
$R-CONH_2 + Br_2 + 4NaOH \rightarrow R-NH_2 + Na_2CO_3 + 2NaBr + 2H_2O$

The resulting primary amine contains one carbon atom less than the parent amide due to the loss of the carbonyl carbon as sodium carbonate. Thus, it is the most convenient method to prepare an amine containing one carbon atom less than the parent compound.

Answer: Hofmann bromamide reaction