This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrine, Subject name: Pharmacology
Based on the given mechanism of action as shown in the Figure, Drug A is likely to be: 
Select and explain. 
A. Exenatide, B. Vildagliptin, C. Canagliflozin, D. Pramlintide
B: Vildagliptin
Answer: B: Vildagliptin 
Explanation: Parasympathetic nerve supply is richly suuplied to Gastrointenstinal tract(GIT). It helps in peristalsis, digestion,motility and absorption of nutrients.