**Core Concept**
The perforation of the appendix is a serious complication that can occur in appendicitis. It is primarily due to the ischemia of the appendix, which leads to a loss of blood supply and subsequent necrosis of the appendiceal wall, ultimately resulting in perforation.

**Why the Correct Answer is Right**
The frequent mechanism in perforation of the appendix is due to the obstruction of the appendix lumen, which leads to a buildup of bacteria, gas, and fluid. This results in increased pressure within the appendix, causing the blood vessels to constrict and ultimately leading to ischemia. The lack of blood supply to the appendix wall causes it to become necrotic, leading to perforation. The most common cause of obstruction is a fecalith, a hard, compact mass of fecal material that blocks the lumen of the appendix.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because while lymphoid hyperplasia can contribute to the narrowing of the appendix lumen, it is not the primary cause of perforation.
**Option B:** This option is incorrect because while a diverticulum can cause a localized area of ischemia, it is not the most common mechanism of perforation.
**Option C:** This option is incorrect because while an abscess can form as a result of perforation, it is not the cause of perforation itself.

**Clinical Pearl / High-Yield Fact**
It is essential to remember that the presence of a fecalith is a strong indicator of appendicitis and can contribute to the development of perforation. A high index of suspicion for appendicitis in patients with a fecalith on imaging is crucial to prevent delayed diagnosis and treatment.

**Correct Answer: C. Ischemia due to obstruction**