A researcher is using Edman degradation to sequence a peptide. What is the sequence of steps they should follow?

• A. Sequentially remove and identify the N-terminal amino acid, repeating the process for each subsequent residue.
• B. Use chemical cleavage to break the peptide into fragments, then sequence each fragment.
• C. Hydrolyze the peptide into free amino acids and determine their composition.
• D. Simultaneously remove all amino acids and identify them using mass spectrometry.

Answer: (A)