**Core Concept**
The nephron's ability to reabsorb potassium ions is crucial for maintaining electrolyte balance in the body. Potassium reabsorption occurs mainly in the **late distal tubule and collecting duct** under the influence of aldosterone.

**Why the Correct Answer is Right**
In the late distal tubule and collecting duct, potassium ions are reabsorbed into the bloodstream in exchange for sodium ions. This process is facilitated by the **Na+/K+-ATPase pump** in the basolateral membrane of the collecting duct cells. The hormone **aldosterone** stimulates this pump, promoting potassium reabsorption and sodium retention. The reabsorption of potassium in this segment is also influenced by **factors such as potassium intake, acid-base balance, and circulating levels of aldosterone**.

**Why Each Wrong Option is Incorrect**
* **Option A:** The proximal convoluted tubule is primarily involved in the reabsorption of glucose, amino acids, and other nutrients. Although some potassium is reabsorbed here, it is not the primary site.
* **Option B:** The loop of Henle is mainly responsible for water and salt reabsorption, with minimal potassium reabsorption occurring in this segment.
* **Option D:** The glomerulus is the initial filtration site, where potassium ions are filtered from the blood into the nephron. However, it is not a site of active reabsorption.

**Clinical Pearl / High-Yield Fact**
Aldosterone levels are often elevated in patients with primary aldosteronism, leading to excessive potassium reabsorption and hypokalemia. This condition can be diagnosed using the **renin-aldosterone ratio**, which helps differentiate primary aldosteronism from other causes of hypertension.

**Correct Answer:** C.