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 break up time test is performed to evaluate the function of: 
Select and explain. 
A. Lacrimal gland, B. Submandibular gland., C. Parotid gland., D. All of the above.
A: Lacrimal gland
Answer: A: Lacrimal gland 
Explanation: The break uptime test is performed to evaluate the function of Lacrimal gland.