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: Pediatrics
Pseudohermaphroditism in a female child is most commonly due to – 
Select and explain. 
A. 21–hydroxylase deficiency, B. 17–hydroxylase deficiency, C. 11–hydroxylase deficiency, D. 3–hydroxylase deficiency
A: 21–hydroxylase deficiency
Answer: A: 21–hydroxylase deficiency 
Explanation: Classic 21-hydroxylase deficiency is the most common cause of Ambiguous genitalia in a newborn.
Virilization is usually apparent at birth in females i.e Pseudohermaphroditism of a female child.