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 drug is contraindicated in liver disease? 
Select and explain. 
A. Sitagliptin, B. Saxagliptin, C. Vildagliptin, D. Alogliptin
C: Vildagliptin
Answer: C: Vildagliptin 
Explanation: Viidagliptin is a DPP - 4 inhibitor which can lead to hepatotoxicity.