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
Investigation of choice for diagnostic evaluation of hydrocephalus in one month old child : 
Select and explain. 
A. X-ray skull, B. USG, C. CT, D. MRI
B: USG
Answer: B: USG 
Explanation: Investigation of choice for hydrocephalus in infant is USG.