**Core Concept**
Typhoid ulcer is a complication of typhoid fever, caused by Salmonella Typhi infection. The ulceration is due to the invasion of the bacteria into the intestinal mucosa, leading to inflammation and necrosis. The location of the ulcer is crucial in determining the risk of rupture.

**Why the Correct Answer is Right**
The typhoid ulcer typically ruptures through the anterior wall of the ileum, which is the part of the small intestine. This is due to the weakening of the intestinal wall as a result of the inflammatory process. The rupture of the ulcer can lead to peritonitis, a life-threatening condition. The location of the rupture is often near the ileocecal junction, where the ileum meets the large intestine.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the typhoid ulcer does not typically rupture through the posterior wall of the ileum.
**Option B:** This option is incorrect because the typhoid ulcer does not typically rupture through the wall of the colon.
**Option D:** This option is incorrect because the typhoid ulcer does not typically rupture through the wall of the stomach.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that the location of the typhoid ulcer is critical in determining the risk of rupture and the subsequent complications. The ileocecal junction is a common site for the rupture of the ulcer, and surgeons should be aware of this when performing surgical interventions.

**Correct Answer:** C.