This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Normal Menstruation, Abnormal Menstruation, Menopausal Physiology and forsight of conception, Subject name: Gynaecology & Obstetrics
[{'content': 'The increasing order of potency of estrogens is (least potent to most potent) ? \nSelect and explain. \nA. E1,E2,E3, B. E1,E3,E2, C. E3, E1, E2, D. E2, E1, E3', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Estradiol (E2) is most potent, followed by Estrone (E1), and Estriol (E3) is least potent', 'role': 'assistant'}]