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 agents is not used in the treatment of Diabetic Macular Edema/Retinopathy – \nSelect and explain. \nA. Ruboxistaurim, B. Pyridazinones, C. Benfotiamine, D. Tamoxifen', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Tamoxifen is known to cause retinopathy and macular edema as an adverse effect. It is not used in the treatment of diabetic macular edema or retinopathy.\nRuboxistaurin, pyridazinones and benfotiamine are all emerging drugs being investigated for treatment of diabetic retinopathy.', 'role': 'assistant'}]