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
Salivary gland stone most commonly involves 
Select and explain. 
A. Submandibular gland, B. Parotid gland, C. Sub lingual glands, D. Lingual glands
A: Submandibular gland
Answer: A: Submandibular gland 
Explanation: None