The exact sequence of events during the digestion of protein is:

• A
  Proteins $\to$ peptones $\to$ acid metaproteins and peptides
• B
  Proteins $\to$ proteoses and peptones $\to$ peptides $\to$ amino acids
• C
  Proteins $\to$ acid metaproteins $\to$ proteoses $\to$ amino acids $\to$ peptides
• D
  Proteins $\to$ primary proteins $\to$ peptides $\to$ amino acids