Most electrolyte reabsorption by the renal tubules is:

Focus on the proximal convoluted tubule: This is the primary site for reabsorption of electrolytes, glucose, amino acids, and water. Reabsorption here is an active process, meaning it requires energy (ATP) to transport substances against their concentration gradient.

Differentiate between active and passive processes: Active transport involves energy expenditure, while passive transport relies on diffusion or osmosis. Electrolyte reabsorption in the proximal convoluted tubule is active, whereas some passive processes occur in other parts of the nephron, like the distal convoluted tubule.