This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: COPD and Asthma, Subject name: Medicine
[{'content': 'Which one of the following is not recommended for the immediate treatment of acute severe asthma? \nSelect and explain. \nA. Iptratropium, B. Magnesium sulfate, C. Hydrocoisone, D. Salmeterol', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Due to slow onset of action , Salmeterol would not be useful .Ipratropium is an anti-cholinergic drug and is useful nebulization. Magnesium sulphate has been used in nebulization form ( surprisingly) or intravenous and antagonizes the effect of intra-cellular calcium. Hence it can reduce the bronchospasm Its used has been mentioned in current edition of Harrison. Hydrocoisone accentuates the effect of broncho-dilators and also inhibit production of leukotrienes.', 'role': 'assistant'}]