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: Pharmacology
Zafirlukast acts by blocking the action of : 
Select and explain. 
A. Prostacyclin, B. Platelet activating factor, C. Leukotriene B4, D. Leukotriene C4/D4
D: Leukotriene C4/D4
Answer: D: Leukotriene C4/D4 
Explanation: None