Chemistry - Nomenclature Question with Solution | TestHub

The principal functional group is the amide (-CONH₂), so the parent chain is the longest chain that contains it, numbered from the end that gives it the lowest locant. Substituents and multiple bonds then take their locants and are written in alphabetical order.

Name: N-ethyl-N-methylpropanamide. The other options use wrong numbering, the wrong alphabetical order or the wrong parent chain.