Where does potassium absorption primarily take place?

Potassium absorption primarily takes place in the small intestine. This organ is responsible for the majority of nutrient absorption in the digestive system, including electrolytes like potassium. As food progresses through the small intestine, potassium is absorbed into the bloodstream along with other nutrients.

While the proximal tubule of the nephron does handle some potassium transport, it is more involved in the regulation of electrolyte balance and reabsorption of filtered potassium rather than being the main site for absorption from the diet. The large intestine plays a minimal role in potassium absorption but can absorb some potassium present in the remaining chyme. The distal colon also has some capacity to absorb potassium, especially when dietary intake is low, but it is primarily responsible for fine-tuning potassium balance rather than being the main site of absorption. Therefore, the small intestine is the site where most dietary potassium is absorbed, aligning with the correct answer.