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': "Dislocation of lens is seen in all the following conditions except : \nSelect and explain. \nA. Congenital Rubella, B. Marchesani's Syndrome, C. Marfan Syndrome, D. Homocystinuria", 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. Congenital Rubella', 'role': 'assistant'}]