Ans. C. The lack of testosterone actiona. The female phenotype can develop in an XY male if the biological action of testosterone is absent. This absence can be due to a lack of testosterone secretion caused by enzyme deficiencies or a lack of the testosterone (DHT) receptor. In this process, called testicular feminization, a phenotypic female develops in the presence of an XY karyotype.b. There is a lack of pubic and axillary hair, well-developed breasts (as a result of the conversion of testosterone to estrogen), with inguinal or abdominal testes, no uterus (because AMH is secreted), underdeveloped male accessory ducts (lack of testosterone action), and the vagina ends in a blind pouch.c. Progesterone has no effect on phenotype. There is no evidence that adrenal insufficiency (low cortisol and androgens from the adrenals) have any effect on inducing female phenotype in a male.d. Inhibin would reduce FSH secretion and ultimately reduce adult testis size, but in the fetus there is no effect on the development of the female phenotype. AMH will prevent formation of the oviducts, uterus, and upper vagina; it does not increase female characteristics in the male.