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
The type of estrogen found in highest concentration in adult female is- 
Select and explain. 
A. Estrone, B. Estriol, C. Estradiol, D. None
C: Estradiol
Answer: C: Estradiol 
Explanation: 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