This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
[{'content': 'Drug used for acute severe asthma is \nSelect and explain. \nA. MGS04, B. Cromolyn sodium, C. Anti leukotriene, D. Cyclosporine', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Magnesium produce broncho dilatationRef:Harrison 17th ed Pg 1605', 'role': 'assistant'}]