In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.
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Question: Question: Statins are used to reduce cholesterol levels and act as analogs of the transition state of an enzyme involved in its biosynthesis. What enzyme is it? 
 Options:  <1> 14-Alpha-demethylase. <2> Hydroxymethylglutaryl coenzyme A (HMGCoA) reductase. <3> Cyclooxygenase 2 (COX-2). <4> Squalene epoxidase. <5> Aromatase

Answer: 2


Question: Question: The demographic dynamics of a community is determined by: 
 Options:  <1> Natality <2> Mortality. <3> Immigration. <4> Emigration. <5> All are correct.

Answer: 5


Question: Question: Does not block the flow of electrons in oxidative phosphorylation: 
 Options:  <1> Cyanide. <2> Antimycin A. <3> CO. <4> 2,4-DNP. <5> Amital.

Answer:
4