**Question:** Most common cause of hemobilia is:

A. Biliary tract injury due to endoscopy
B. Liver abscess
C. Angiography
D. Choledocholithiasis

**Core Concept:** Hemobilia refers to the presence of blood in the bile ducts, typically resulting from bleeding within or near the biliary system. It can be caused by various factors, including direct biliary tract injury, choledocholithiasis, angiographic procedures, and liver abscesses.

**Why the Correct Answer is Right:** The correct answer, C. Angiography, is due to the fact that angiography is a common imaging procedure that involves the injection of contrast material into blood vessels to visualize blood vessels and their structures. In this process, there is a possibility of iatrogenic injury to the biliary tract, resulting in hemobilia.

**Why Each Wrong Option is Incorrect:**

A. Biliary tract injury due to endoscopy (Option A) is less common compared to angiographic procedures like angiography.
B. Liver abscess (Option B) can cause hemobilia due to sepsis and inflammation, but it is less likely as the primary cause compared to angiography.
D. Choledocholithiasis (Option D) can lead to hemobilia due to the presence of gallstones obstructing the bile ducts, but it is less likely as the primary cause compared to angiography.

**Clinical Pearl:** Angiography is a critical diagnostic tool in medicine, but it is essential for healthcare professionals to be aware of the risk of iatrogenic biliary tract injury during this procedure. Physicians should take appropriate precautions, such as using appropriate techniques and ensuring patient positioning to minimize the risk of biliary tract injury and hemobilia.