This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology and Reproduction, Subject name: Physiology
[{'content': 'The type of estrogen found in highest concentration in adult female is- \nSelect and explain. \nA. Estrone, B. Estriol, C. Estradiol, D. None', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans (c) Estradiol(Ref: Ganong, 25th ed/p.406)Naturally occurring estrogens are,Estradiol (E2 ) - predominant estrogen during reproductive yearsEstrone (E1) - predominant estrogen in menopausal womenEstriol (E3) - predominant estrogen in pregnant women', 'role': 'assistant'}]