This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Pharmacology
Mechanism of action of statins is by: 
Select and explain. 
A. Competitive inhibition, B. Noncompetitive inhibition, C. Uncompetitive, D. Irreversible inhibition
A: Competitive inhibition
Answer: A: Competitive inhibition 
Explanation: Ref: Goodman & Gillman's 13th ed. P 609* Statins exert their major effect--reduction of LDL levels--through a mevalonic acid-like moiety that competitively inhibits HMG-CoA reductase, which is the rate limiting enzyme in the cholesterol biosynthesis.* Drugs are atorvastatin, rosuvastatin, fluvastatin, lovastatin, pravastatin, simvastatin, pitavastatin.* Food increases absorption of statins* Statins are most active at night, so given at night except rosuvastatin and atorvastatin which are longest acting statins.