**Core Concept**
Biliary obstruction can be caused by various factors, including gallstones, tumors, and anatomical abnormalities. The liver produces bile, which is stored in the gallbladder and released into the bile ducts to flow into the small intestine. Obstruction at any point in this pathway can lead to jaundice, abdominal pain, and other complications.

**Why the Correct Answer is Right**
The correct answer is not listed, so we will go through each option. However, we can still explain why each option might be incorrect.

**Why Each Wrong Option is Incorrect**
* **Option A:** Not provided.
* **Option B:** Not provided.
* **Option C:** Not provided.
* **Option D:** Not provided.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that biliary obstruction can be caused by both intrinsic and extrinsic factors. Intrinsic factors include gallstones, tumors, and strictures, while extrinsic factors include external compression by adjacent organs or structures.

**Correct Answer:** Not provided.