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: Pharmacology
Which of the following is excreted in saliva ? 
Select and explain. 
A. Tetracyclines, B. Ampicillin, C. Lithium, D. Chloramphenicol
C: Lithium
Answer: C: Lithium 
Explanation: None