**Core Concept**
G6PD deficiency is a condition where the enzyme glucose-6-phosphate dehydrogenase is deficient, leading to oxidative stress and hemolysis in red blood cells. Certain drugs can trigger hemolysis in individuals with G6PD deficiency by generating reactive oxygen species (ROS) that deplete NADPH and disrupt the antioxidant defense system in erythrocytes.

**Why the Correct Answer is Right**
The correct answer is **Primaquine** is not listed, however, the correct answer is **C. Chloroquine** does cause hemolysis but it's not the correct answer here. **Primaquine** is known to cause hemolysis in G6PD deficiency patients due to its ability to generate ROS, which damages the red blood cells. However, **Nitrofurantoin** does not cause hemolysis in G6PD deficiency patients, as it does not significantly generate ROS that can lead to oxidative stress in erythrocytes.

**Why Each Wrong Option is Incorrect**
**Option A:** **Primaquine** does cause hemolysis in G6PD deficiency patients, making it an incorrect option.
**Option B:** Not listed, however, **Chloroquine** can cause hemolysis in G6PD deficiency patients, so it would be an incorrect option. However, the question is asking which drug does not cause hemolysis in G6PD deficiency, making this option not relevant.
**Option D:** **Sulfonamides** can also cause hemolysis in G6PD deficiency patients by generating ROS and depleting NADPH, making it an incorrect option.

**Clinical Pearl / High-Yield Fact**
When prescribing medications to patients with G6PD deficiency, it's essential to choose drugs that are G6PD-compatible to avoid triggering hemolysis.

**Correct Answer: C. Nitrofurantoin. Nitrofurantoin**