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: Surgery
In gallbladder mucocoele where is the stone usually impacted 
Select and explain. 
A. Hartmann's pouch, B. Calot's triangle, C. CBD, D. Duodenum
A: Hartmann's pouch
Answer: A: Hartmann's pouch 
Explanation: None