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
A male infant is brought to the emergency with vomiting, lethargy, dehydration and  features of shock. clinical examination reveals hyperpigmentation of genital skin and normal external genitalia. Blood investigation reveal sodium 124mg/L. Potassium 7 meq / L hypoglycemia. what is the most probable diagnosis? 
Select and explain. 
A. Adrenal hemorrhage, B. Congenital adrenal hyperplasia(CAH), C. Acute Gastroenteritis with dehydration, D. Hyperaldosteronism
B: Congenital adrenal hyperplasia(CAH)
Answer: B: Congenital adrenal hyperplasia(CAH) 
Explanation: None