This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous system, Subject name: Pathology
Cause (s) of secondary brain injury is/are- 
Select and explain. 
A. Pyrexia and hypotension, B. Seizures and metabolic disturbance, C. Low cerebral perfusion pressure, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Secondary brain injury refers to the changes that evolve over a period of time (from hours to days) after the primary brain injury. Primary and secondary brain injury are ways to classify the injury processes that occur in brain injury. Examples in traumatic brain injury Primary Secondary Intracerebral hemorrhage Subdural hemorrhage Subarachnoid hemorrhage Epidural hemorrhage Cerebral contusion Cerebral laceration Axonal stretch injury. Cerebral edema Impaired metabolism Altered cerebral blood flow Free radicalformation Excitotoxicity