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: Surgery
An elderly man who has had a trival history of head injury three months ago, develops headache and turns unconscious. On examination, he is found to have fixed left dilated pupil and right hemiplegia. What is the most likely diagnosis 
Select and explain. 
A. Contusio-cereberi, B. Extradural hematoma, C. Chronic subdural hematoma, D. Brain abscess
C: Chronic subdural hematoma
Answer: C: Chronic subdural hematoma 
Explanation: None