Which system is responsible for eliminating waste from the circulatory system and balancing water in the body?

The urinary system plays a crucial role in maintaining the body's homeostasis by filtering blood and removing waste products through urine. It consists of the kidneys, ureters, bladder, and urethra. The kidneys are particularly important, as they filter excess substances, toxins, and metabolic waste from the bloodstream while also regulating electrolyte levels and maintaining the balance of water.

This process helps manage the volume of blood and fluid in the body, contributing to blood pressure regulation and ensuring that the body's internal environment remains stable. Therefore, the urinary system is essential not only for waste elimination but also for water balance, making it the correct answer to the question.

In contrast, the respiratory system primarily handles gas exchange, including the removal of carbon dioxide, while the nervous system coordinates body functions and responses. The digestive system is involved in breaking down food and absorbing nutrients but does not deal directly with the circulatory system's waste management and water balance.