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: Medicine
Which of the following drugs is used for Irritable Bowel Syndrome of the constipating type - 
Select and explain. 
A. Lubipro stone, B. Cholestyramine, C. Alosetron, D. Rifaximin
A: Lubipro stone
Answer: A: Lubipro stone 
Explanation: None