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': 'Painful loss of vision is seen in –a) Senile cataractb) Primary open angle glaucomac) Primary angle closure glaucomad) Anterior uveitis \nSelect and explain. \nA. ab, B. cd, C. bd, D. ac', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Causes of sudden painful loss of vision are:- Acute angle-closure glaucoma, acute iridocyclitis (acute uveitis), chemical or mechanical injury to eye, endophthalmitis and optic neuritis.', 'role': 'assistant'}]