## **Core Concept**
The question tests knowledge of the history of pharmacology, specifically the development of H2 receptor blockers. H2 receptor blockers are a class of medications that reduce the amount of acid produced by the stomach. They work by blocking histamine H2 receptors in the stomach lining.

## **Why the Correct Answer is Right**
The correct answer, **C. Sir James Black**, is credited with the development of the first H2 receptor blocker, cimetidine, which was synthesized in 1972. Sir James Black was a Scottish physician and pharmacologist who was awarded the Nobel Prize in Physiology or Medicine in 1987 for his discoveries of important principles of drug treatment. Cimetidine was a significant breakthrough in the treatment of peptic ulcers and gastroesophageal reflux disease (GERD).

## **Why Each Wrong Option is Incorrect**
* **Option A:** Not provided, but typically would be an incorrect name or date.
* **Option B:** Not provided, but would represent another incorrect choice.
* **Option D:** Not provided, but another incorrect option.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that H2 receptor blockers like cimetidine have been largely superseded by proton pump inhibitors (PPIs) for the treatment of acid-related gastrointestinal disorders, due to their more potent and longer-lasting effects.

## **Correct Answer:** C. Sir James Black