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 function in Sjogren syndrome patients is measured by: 
Select and explain. 
A. Salivary flow rate., B. Minor salivary gland biopsy., C. Salivary scintigraphy., D. All of the above.
D: All of the above.
Answer: D: All of the above. 
Explanation: None