Teacher:Given a scientific passage and an answer, generate a question for the given answer.
Teacher: Now, understand the problem? Solve this instance: Passage: The boy in Figure below is working out on a hot day. He's losing a lot of water in sweat. To maintain homeostasis, his body can balance the water lost in sweat by excreting less water in urine. The amount of water lost in urine is controlled by the kidneys. The kidneys are organs of excretion. Answer: kidneys
Student:
Which organ in the body controls the amount of water loss in urine in response to maintaining homeostasis?