**Core Concept**
Duodenal blowout, also known as duodenal perforation or duodenal rupture, refers to a life-threatening condition where there is a tear or hole in the wall of the duodenum, the first part of the small intestine. This condition often results from a sudden increase in pressure within the duodenum, which can be caused by various factors such as severe vomiting, abdominal trauma, or underlying medical conditions.

**Why the Correct Answer is Right**
Duodenal blowout typically occurs due to the accumulation of gas within the duodenum, leading to a sudden increase in pressure. This pressure can cause the thin wall of the duodenum to rupture, resulting in leakage of intestinal contents into the abdominal cavity. The condition can be further complicated by the presence of bile and pancreatic enzymes, which can cause severe inflammation and infection.

**Why Each Wrong Option is Incorrect**
* **Option A:** Duodenal diverticulum is a false diverticulum that can cause symptoms similar to duodenal blowout, but it is a distinct clinical entity.
* **Option B:** Duodenal ulcer is a peptic ulcer that can cause perforation, but it is a different condition from duodenal blowout.
* **Option C:** Duodenal obstruction is a condition where the flow of intestinal contents is blocked, but it is not the same as a perforation.

**Clinical Pearl / High-Yield Fact**
Duodenal blowout is a surgical emergency that requires prompt treatment to prevent further complications, including peritonitis and sepsis.

**Correct Answer:** C.