This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
The saliva does NOT contain: 
Select and explain. 
A. Amylase, B. Lysozyme, C. Mucin, D. Hydrochloric acid
D: Hydrochloric acid
Answer: D: Hydrochloric acid 
Explanation: D: Saliva does not contain hydrochloric acid.
A: The serous part of saliva, produced mainly by the parotid and submandibular glands, contains a digestive enzyme called salivary amylase.
B: Saliva prevents bacterial infection in the mouth by washing the oral cavity, and it contains lysozyme, which has a weak antibacterial action.
C: The serous part of saliva dissolves molecules, which must be in solution to stimulate taste receptors. The mucous secretions of the submandibular and sublingual glands contain a large amount of mucin, a proteoglycan that gives a lubricating quality tot he secretions of the salivary glands.