This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
Most common cause of ambigious genitalia in a female child is: 
Select and explain. 
A. Placenta steroid sulfatase deficiency, B. Fetal aromatase deficiency, C. Wnt4 mutation, D. Congenital adrenal hyperplasia
D: Congenital adrenal hyperplasia
Answer: D: Congenital adrenal hyperplasia 
Explanation: “CAH due to 21 hydroxylase deficiency is the most frequent cause of sexual ambiguity and the M/C endocrine cause of neonatal death.”
Ambiguity of sex at birth—"Cases of ambiguity of sex detected at birth are due to adrenogenital syndrome unless proved otherwise".