**Question:** Annular pancreas, true is -

A. Part of the pancreas that surrounds the duodenum
B. A congenital abnormality resulting in a horseshoe-shaped pancreas
C. A type of pancreatic insufficiency
D. A rare pancreatic cyst

**Core Concept:**
Annular pancreas is a congenital anomaly characterized by a horseshoe-shaped pancreas that encircles the second part of the duodenum. This condition is caused by incomplete separation of the dorsal and ventral pancreatic buds during embryonic development.

**Why the Correct Answer is Right:**
The correct answer is B because annular pancreas refers to a specific congenital anomaly involving the pancreatic structure. It is characterized by a horseshoe-shaped pancreas that encircles the second part of the duodenum due to incomplete separation of the dorsal and ventral pancreatic buds during embryonic development. This abnormality can lead to potential complications like pancreaticobiliary reflux and cholangitis.

**Why Each Wrong Option is Incorrect:**
A and C are incorrect because annular pancreas is a congenital anomaly, not a part of the pancreas or a form of pancreatic insufficiency. D is incorrect as annular pancreas primarily affects the structure of the pancreas, not a pancreatic cyst.

**Clinical Pearl / High-Yield Fact:**
Annular pancreas is a rare condition with an estimated incidence of 0.04% to 0.4%. A definitive diagnosis can be made through imaging studies such as computed tomography (CT) scans or magnetic resonance cholangiopancreatography (MRCP). Early recognition and management of complications are crucial to prevent serious consequences.