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: Radiology
Antenatal diagnosis of hydrocephalus is done by: 
Select and explain. 
A. USG, B. AFP estimation, C. Foetoscopy, D. Aminocentesis
A: USG
Answer: A: USG 
Explanation: Ans. USG