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: Pharmacology
[{'content': 'Which of the following drug is not used in glaucoma: \nSelect and explain. \nA. Pilicarpine., B. Physostigmine., C. Metoprolol., D. Timolol.', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Metoprolol is a beta blocker with local anaesthetic activity which cannot be used in glaucoma.', 'role': 'assistant'}]