What is dialysis used for?

Dialysis is a medical treatment specifically designed to perform the essential functions of the kidneys when they are no longer able to effectively filter waste products from the blood. This includes the removal of excess fluids, electrolytes, and toxins that can accumulate in the body due to kidney dysfunction. By mimicking the filtration process of healthy kidneys, dialysis helps to maintain the body's chemical balance and overall homeostasis, preventing complications associated with renal failure.

The other options do not accurately reflect the purpose of dialysis. Enhancing metabolic rate is not a function of dialysis; rather, it is more related to different physiological processes and may involve other interventions. Promoting muscle recovery is typically associated with physical therapy and proper nutrition, while delivering nutrients to patients is done through nutritional support methods such as intravenous feeding or enteral nutrition, rather than dialysis. Thus, option B is clearly the most relevant and correct choice in the context of kidney dysfunction and the role of dialysis in patient care.