This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autonomic nervous system, Subject name: Pharmacology
[{'content': "Edrophonium test is helpful in diagnosing \nSelect and explain. \nA. Marcus gunn jaw winking ptosis, B. myasthenia gravis, C. Blepharophismosis syndrome, D. parkinson's", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ref: HL Sharma 3rd ed pg no: 142 edrophonium is very sho acting which helps in differentiating myasthenia and cholinergic crisis', 'role': 'assistant'}]