All of the following are natural estrogens except ?: (A) Estradial, (B) Ethinylestradiol, (C) Estriol, (D) Estrone
Answer is B. Ans. is 'b' i.e., Ethinylestradiol o Estradial, estrone and estrial, all three are found in blood, but estradiol is the most potent estrogen.