This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
[{'content': 'Most Impoant hormone responsible for volume maintenance? \nSelect and explain. \nA. Aldosterone, B. Angiotensin, C. ADH, D. Renin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. is \'c\' i.e., ADH[Rel Principles of medical physiology p. 412; Ganong 2,{h/e p. 7041"Despite its effect on Na* and water reabsorption, aldosterone k a weak regulator of boily Na+ and water balance, the majorregulator being the \'thirst-ADH\' mechanism, Aldosterone k the sole regulator of external potassium balance\'.- Principles of medical physiology', 'role': 'assistant'}]