The reaction of aliphatic and aromatic primary amines with chloroform in the presence of ethanolic potassium hydroxide to produce compound with fouling smell, is known as

Carbylamine reaction

The correct answer is Option (2) → Carbylamine reaction

Primary amines when heated with chloroform ($CHCl_3$) and alcoholic KOH produce isocyanides (carbylamines), which have a very foul smell.

General reaction:

$R-NH_2+ CHCl_3 + 3KOH → R-NC + 3KCl + 3H_2O$

This reaction is used as a test for primary amines and is known as the Carbylamine reaction.

Option 1: Rosenmund reaction

Used for conversion of acid chloride to aldehyde using $Pd/BaSO_4$. Not related to amines.

Option 2: Carbylamine reaction

Primary amines react with $CHCl_3$ and alcoholic KOH to give isocyanides with foul smell. Correct.

Option 3: Fittig reaction

Coupling of aryl halides using sodium in dry ether. Not related to amines.

Option 4: Etard reaction

Oxidation of toluene to benzaldehyde using chromyl chloride. Not related to amines.