Ans. is b, i.e. Perform a karyotype1st step in primary amenorrhea is to identify the site of lesion by doing Hormonal profileIn question : LH and FSH are highUSG: shows uterus and vagina are presentPt has short height (4 feet)No secondary sexual characteristicsNow since LH and FSH are high and estrogen is low (as secondary sexual characteristics are absent)[?] It is a case of hypergonadotropic hypogonadism --so most probably it is Turners syndrome. This can be confirmed by doing karyotyping.Always remember in Primary amenorrhea1st Test: Hormonal ProfileBest Test: Karyotyping