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
Which of the following drug inhibits the enzyme of initial step of cholesterol synthesis ? 
Select and explain. 
A. Lovastatin, B. Gemfiberozil, C. Probucol, D. Cholestyramine
A: Lovastatin
Answer: A: Lovastatin 
Explanation: Ans. is 'a' i.e., Lovastatin o Statins (Lovastatin) competitively inhibit the conversion of HMG-CoA to mevalonate (rate limiting step in cholesterol synthesis) by inhibiting the enzyme HMG-CoA reductase.