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: Ophthalmology
[{'content': 'Which of the following is not useful in chronic open angle glaucoma: \nSelect and explain. \nA. Prostagladin analogue, B. Pilocarpine, C. Homatropine, D. Timolol', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C: Homatropine Medical therapy for primary open angle glaucoma includes: 1st line-Beta blockers (timolol), brimonidine, prostaglandin analogues; Adjunctive-Dipivefrine, dorzolamide, pilocarpine', 'role': 'assistant'}]