Which of the following definitions matches the term "isotonic?

A. Intravenous solutions are less concentrated than blood and other body fluids. These solutions are used to treat a fluid and electrolyte imbalance by moving water into the cells is incorrect because this describes hypotonic solutions, which move water into cells and are less concentrated than plasma. B. Solution that has the same concentration of solutes as human blood is correct because isotonic solutions have an osmolarity equal to that of plasma. They do not cause significant fluid shifts between the intracellular and extracellular compartments, making them ideal for fluid replacement and maintaining vascular volume. Common examples include 0.9% sodium chloride (normal saline) and lactated Ringer’s solution. C. Intravenous solutions are more concentrated than body fluids. They pull fluid from the interstitial spaces and cells into the veins is incorrect because this defines hypertonic solutions, which draw water out of cells into the intravascular space. D. Administration of a small volume of intravenous solution, connected to and hung higher than a primary intravenous solution is incorrect because this describes a secondary IV (piggyback) infusion, which refers to the method of administration, not the tonicity of the solution.