Write IUPAC names for the following carboxylic acid derivatives. If possible, write common names too.

• A. A: IUPAC Name: N-phenylmethanamide
  Common Name: N-phenyl formamide
  B: IUPAC Name: 2-methylpropanamide
  Common Name: isobutyramide
  C: IUPAC Name: N-methylbutanamide
  Common Name: N-methyl butyramide
• B. A: IUPAC Name: phenylmethanamide
  Common Name: phenyl formamide
  B: IUPAC Name: 2-methylpropanamide
  Common Name: isobutyramide
  C: IUPAC Name: methylbutanamide
  Common Name: methyl butyramide
• C. A: IUPAC Name: N-phenylmethanoic amide
  Common Name: N-phenyl formamide
  B: IUPAC Name: 2-methylpropanamide
  Common Name: isobutyramide
  C: IUPAC Name: N-methylbutanamide
  Common Name: N-methyl butyramide
• D. A: IUPAC Name: N-phenylmethanamide
  Common Name: N-phenyl formamide
  B: IUPAC Name: 2-methylpropanamide
  Common Name: isobutyramide
  C: IUPAC Name: N-methylbutanamine
  Common Name: N-methyl butyl amide

Answer: (A)