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 drugs promotes the release of endogenous insulin ? 
Select and explain. 
A. Acarbose, B. Glipizide, C. Metformin, D. Pioglitazone
B: Glipizide
Answer: B: Glipizide 
Explanation: None