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
Mechanism of action of aspirin as antiplatelet drug is it's inhibitory action on 
Select and explain. 
A. Prostacyclins, B. PGF-2 alpha, C. Thromboxane A2, D. Phospholipase C
C: Thromboxane A2
Answer: C: Thromboxane A2 
Explanation: Refer KDT 7th /629 By inhibiting cyclooxygenase enzyme, aspirin initially decreses6 the level of both prostacyclins and TXA2 Howevr6 after some time prostacyclins synthesis resumes due to presence big nulcues in endothelium where'ass TXA2 remain depressed because platelets are enucleated