**Core Concept**
The question pertains to the typical anatomical location of chronic gastric ulcers, which is a critical aspect of gastroenterology and internal medicine. Gastric ulcers are mucosal defects in the stomach lining, often resulting from Helicobacter pylori infection, nonsteroidal anti-inflammatory drug (NSAID) use, or other factors.

**Why the Correct Answer is Right**
The most common location of chronic gastric ulcers is the lesser curvature of the stomach, particularly in the prepyloric region. This area is prone to ulceration due to factors such as increased acid production, reduced blood flow, and the presence of Helicobacter pylori. The prepyloric region is characterized by the presence of the antrum, which is a narrow, muscular portion of the stomach that plays a crucial role in the regulation of gastric emptying.

**Why Each Wrong Option is Incorrect**
**Option A:** The posterior wall of the stomach is a less common location for gastric ulcers, as it is less exposed to acid and pepsin.
**Option B:** The fundus of the stomach is not a typical location for chronic gastric ulcers, as it is primarily involved in the storage of food and secretion of mucus.
**Option C:** The duodenum is a common location for peptic ulcers, but it is not a typical location for gastric ulcers, which are confined to the stomach lining.

**Clinical Pearl / High-Yield Fact**
The "clock face" method is a useful tool for localizing gastric ulcers, with the lesser curvature corresponding to the 6 o'clock position and the antrum corresponding to the 12 o'clock position.

**Correct Answer: C. Duodenum.**