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: Dental
Saliva produced during stimulation by eating or by mechanical manipulation during dental procedures arises principally from the: 
Select and explain. 
A. Minor salivary glands., B. Submandibular, sublingual and minor salivary glands., C. Submandibular glands., D. Sublingual glands.
C: Submandibular glands.
Answer: C: Submandibular glands. 
Explanation: The total volume of saliva secreted by humans is approximately 750 to 1000 ml daily, of which submandibular accounts for 60%, the parotid about 30% and the sublingual about 5% or less, and about 1% of saliva is derived from the minor salivary glands.