**Core Concept**
Furosemide is a loop diuretic that works by inhibiting the Na+-K+-2Cl- cotransporter (NKCC2) in the thick ascending limb of the loop of Henle. This action leads to increased urinary excretion of sodium, potassium, chloride, and water.

**Why the Correct Answer is Right**
Furosemide's mechanism of action involves the inhibition of the NKCC2 cotransporter, which is responsible for reabsorbing sodium, potassium, and chloride ions in the thick ascending limb of the loop of Henle. This inhibition leads to a decrease in the reabsorption of these ions, resulting in their increased excretion in the urine. Consequently, furosemide promotes the excretion of water, sodium, potassium, and chloride, making it an effective diuretic.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not specify the correct mechanism of action of furosemide.
* **Option B:** This option is incorrect because it is a statement about thiazide diuretics, not loop diuretics like furosemide.
* **Option D:** This option is incorrect because it is a statement about the action of potassium-sparing diuretics, which is not relevant to furosemide.

**Clinical Pearl / High-Yield Fact**
Furosemide can cause a significant loss of potassium ions, which can lead to hypokalemia. Therefore, patients on furosemide should be monitored for potassium levels and potassium supplements may be necessary to prevent hypokalemia.

**Correct Answer: C. Furosemide inhibits the Na+-K+-2Cl- cotransporter in the thick ascending limb of the loop of Henle.**