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
Commonest cause of non-communicating hydrocephalus in children is - 
Select and explain. 
A. Congenital anomaly, B. Perinatal injury, C. Post-inflammatory obstruction, D. Brain tumors
A: Congenital anomaly
Answer: A: Congenital anomaly 
Explanation: Ans. is 'a' i.e., Congenital anomaly Hydrocephalus o Hydrocephalus is characterized by an increased volume of CSF in association with progressive ventricular dilatation. o Hydrocephalus resulting from obstruction within the ventricular system is called obstructive or noncommunicating hydrocephalus. o Hydrocephalus resulting from obliteration of subarachnoid cisterns or malfunction of the arachnoid villi is called nonobstructive or communicating hydrocephalus.