<prompt> The commonest cause of primary amenorrhea with ambiguous genitalia in a female with 46XX chromosome :21 hydroxylase def.17 hydroxylase def.11 hydroxylase def.Desmolase hydrolase def  <response>: A i.e. 21- hydroxylase deficiencyClassic 21 - hydroxylase deficiency is most common cause of ambiguous genitalia in new born virilization and primary amenorrheaQ. i.e. Pseudohermaphroditism of female childPrimary amenorrhea with VirilizationQ in females is in:- 21 - hydroxylase deficiency- 11 - Hydroxylase deficiencyTypesMain function ofenzymeMineralococoidMGlucocoicoidGAndrogenFeatures21- OH-deficiencyGlucocoicoid Mineralocoicoidproduction Ul HypotensionQsalt losing virilization VirilizationQ in females Precocious pubey in femalesQ.11 hydroxylase-deficiencyGlucocoicoidproductionT.1.1,T HypeensionQ VirilizationQ in females Precocious pubey in femalesQ.17- hydroxylasedeficiencyGlucocoicoid Androgen production1.1,14 Male hermaphroditeQ Primary atnenorrhea infemalesQ. HypeensionQ3 - p-hydroxylasedeficiencyMineralcoicoid glucocoicoidproduction..1,.1,T Male hermaphrodite. 