**Core Concept**
The left gastro-epiploic artery is a branch of the splenic artery, which is a major artery supplying blood to the spleen and stomach. This artery plays a crucial role in the blood supply of the stomach, particularly the greater curvature.

**Why the Correct Answer is Right**
The left gastro-epiploic artery arises from the splenic artery, which is a direct branch of the celiac trunk. The splenic artery then divides into three main branches: the left gastro-epiploic artery, the short gastric arteries, and the splenic artery itself. The left gastro-epiploic artery supplies the greater curvature of the stomach and anastomoses with the right gastro-epiploic artery to form the gastroepiploic arcade.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as the left gastro-epiploic artery does not arise from the hepatic artery proper, which primarily supplies the liver.
* **Option B:** This option is incorrect as the left gastro-epiploic artery does not arise from the superior mesenteric artery, which primarily supplies the small intestine and parts of the large intestine.
* **Option D:** This option is incorrect as the left gastro-epiploic artery does not arise from the right gastro-epiploic artery, which is actually a branch of the gastroduodenal artery.

**Clinical Pearl / High-Yield Fact**
The left gastro-epiploic artery is an important landmark in laparoscopic cholecystectomy, as it is often used to identify the location of the stomach and the hepatic artery proper during dissection.

**Correct Answer: C. The splenic artery.**