Which statement best describes electrolytes in intracellular and extracellular fluid?

Electrolytes are distributed unequally between intracellular and extracellular fluids. Sodium concentration is higher in extracellular fluid, while potassium concentration is higher in intracellular fluid. Therefore, the correct answer is 'There is a greater concentration of sodium in extracellular fluid and potassium in intracellular fluid.' Choices B, C, and D are incorrect because they do not accurately describe the typical distribution of sodium and potassium between intracellular and extracellular fluid.