This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory System, Subject name: Pharmacology
Which of the following drug is a leukotriene receptor antagonist? 
Select and explain. 
A. Nicorandil, B. Zileuton, C. Sodium cromoglycate, D. Montelukast
D: Montelukast
Answer: D: Montelukast 
Explanation: Montelukast and zafirlukast inhibit the bronchoconstrictor action of LTs at cys LT1 receptor. These are used as prophylactic agents for bronchial asthma. These are very safe drugs but few cases of Churg Strauss syndrome (vasculitis with eosinophilia) have been associated with their use.