This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: NSAIDs, Gout and Rheumatoid Ahritis, Subject name: Pharmacology
Aspirin is used in the prophylaxis of myocardial infarction because it results in: 
Select and explain. 
A. Inhibition of thromboxane synthetase, B. Inhibition of cyclooxygenase, C. Decreased serum lipids, D. Coronary steal phenomenon
B: Inhibition of cyclooxygenase
Answer: B: Inhibition of cyclooxygenase 
Explanation: Aspirin acts as an antiplatelet drug in MI. It inhibits cox enzyme and thus reduces the synthesis of TXA2. However it has no effect on the enzyme, thromboxane synthetase. Therefore, answer here is the inhibition of cox.