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
All are used in treatment of Helicobactor pylori, EXCEPT- 
Select and explain. 
A. Colloid bismuth, B. Cisapride, C. Clarithromycin, D. Metronidazole
B: Cisapride
Answer: B: Cisapride 
Explanation: None