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
[{'content': 'Mechanism of action of statins: March 2013 \nSelect and explain. \nA. HMG-CoA synthase stimulator, B. HMG-CoA reductase stimulator, C. HMG-CoA synthase inhibitor, D. HMG-CoA reductase inhibitor', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D i.e. HMG-CoA reductase inhibitor Statins used to lower cholesterol levels, acts by inhibiting the enzyme HMG-CoA reductase', 'role': 'assistant'}]