Pediatrics General c5ca8e6e MC deficient enzyme in Congenital adrenal hyperplasia: March 2013 A 21-hydroxylase deficiency B 18-hydroxylase deficiency C 3-beta-hydroxysteroid dehydrogenase deficiency D 17-alpha hydroxylase deficiency High-Yield Explanation Ans. A i.e. 21-hydroxylase deficiency