This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Drugs, Subject name: Ophthalmology
[{'content': 'Shortest acting mydriatic is? \nSelect and explain. \nA. Tropicamide, B. Atropine, C. Phenylephrine, D. Hyoscine', 'role': 'user'}, {'content': 'Answer: A \nExplanation: ANSWER: (A) TropicamideREF: khurana 4th ed p. 68shortest acting mydriatic - TropicamideOnly mydriatic and not cycloplegic - phenylephrineUsed in children - Atropine', 'role': 'assistant'}]