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 test helps to differentiate between concomitant squint and paralytic squint \nSelect and explain. \nA. Cover - uncover test, B. Alternate covertest, C. Direct cover test, D. None of the above', 'role': 'user'}, {'content': 'Answer: B \nExplanation: This procedure causes breakdown of binocular fusion mechanism thus helpful to differentiate.', 'role': 'assistant'}]