**Core Concept**
The question tests the understanding of diuretic mechanisms, specifically the relationship between natriuresis (sodium excretion) and kaliuresis (potassium excretion). Diuretics act on different parts of the nephron to inhibit sodium reabsorption, which indirectly affects potassium levels.

**Why the Correct Answer is Right**
The correct diuretic causes significant kaliuresis by acting on the ascending loop of Henle, where it inhibits the Na-K-2Cl cotransporter. This action leads to increased sodium delivery to the distal nephron, enhancing potassium secretion. The mechanism involves the **aldosterone-sensitive** part of the collecting duct, where increased sodium reabsorption promotes potassium excretion.

**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because it primarily acts on the proximal tubule with less effect on kaliuresis.
**Option B:** Incorrect as it has a mild effect on potassium excretion compared to the correct answer.
**Option D:** Incorrect because it is known for causing hypokalemia but is not the most potent in terms of kaliuresis per natriuresis.

**Clinical Pearl / High-Yield Fact**
Remember, the diuretic causing the most kaliuresis for a given amount of natriuresis typically acts at the loop of Henle, increasing the risk of hypokalemia.

**Correct Answer:** D. Furosemide