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
[{'content': 'In a patient of head injury which is more important to note first: \nSelect and explain. \nA. Pupillary light reflex, B. Pupillary size, C. Corneal reflex, D. Ability to open eye', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]