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
Biconvex hyperdense shadow on non-contrast CT scan is seen in: 
Select and explain. 
A. Extradural haemorrhage, B. Subdural haemorrhage, C. Subarachnoid haemorrhage, D. Intraventricular haemorrhage
A: Extradural haemorrhage
Answer: A: Extradural haemorrhage 
Explanation: Ans. Extradural haemorrhage