This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Anatomy
Most commonly seen Choledochal cyst 
Select and explain. 
A. Type I, B. Type II, C. Type III, D. Type IV
A: Type I
Answer: A: Type I 
Explanation: Most common Choledochal cyst Type I>Type IV >Type III Type I is the most common It is the dilation of extrahepatic biliary tree Type Ia: cystic dilation Type Ib: Focal segmental dilation Type Ic : Fusiform dilation Treatment : Roux-en-Y hepatic jejunostomy Ref: Sabiston 20th edition 1510-1511