**Core Concept**
Zollinger Ellison syndrome (ZES) is a rare disorder characterized by excessive gastric acid secretion due to high levels of gastrin, a hormone produced by gastrinomas, typically found in the duodenum or pancreas. The pathophysiology involves an abnormal feedback mechanism that leads to hypergastrinemia and subsequent hyperacidity.

**Why the Correct Answer is Right**
The treatment of choice for ZES is proton pump inhibitors (PPIs), which effectively reduce gastric acid secretion by irreversibly inhibiting the H+/K+ ATPase enzyme on the gastric parietal cell surface. This enzyme is responsible for pumping hydrogen ions into the gastric lumen, thereby increasing the acidity of the stomach contents. PPIs are more effective than H2 receptor antagonists in managing ZES due to their potent and long-lasting inhibition of gastric acid secretion.

**Why Each Wrong Option is Incorrect**
**Option A:** Histamine antagonists are not the treatment of choice for ZES, as they are less effective than PPIs in reducing gastric acid secretion. Although histamine stimulates the parietal cells to secrete acid, H2 receptor antagonists only partially inhibit this effect.
**Option B:** Somatostatin analogs may be used adjunctively to control symptoms in ZES, but they are not the primary treatment of choice. These medications reduce gastrin secretion but have variable efficacy and may cause side effects such as cholelithiasis.
**Option C:** Anticholinergics are not effective in treating ZES, as they do not directly address the underlying pathophysiology of hypergastrinemia and acid hypersecretion.

**Clinical Pearl / High-Yield Fact**
In managing ZES, it's essential to remember that PPIs can mask symptoms of the underlying gastrinoma, potentially delaying diagnosis. Regular endoscopic surveillance is crucial to detect any gastrinoma or other complications.

**Correct Answer: C. Proton pump inhibitors (PPIs)**