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: What specific procedure of the experimental strategy makes it the most appropriate to test hypotheses of causality? : 
 Options:  <1> The representative sampling of the participants. <2> The manipulation of the independent variable with control of possible strange variables. <3> The realization of the study in real contexts with natural groups. <4> The identification of possible predictor variables through the retrospective analysis of the study phenomenon. <5> The application of statistical techniques for the analysis of data.

Answer: 2


Question: Question: The diagnostic sensitivity of an analytical magnitude for a certain disease is: 
 Options:  <1> 1 / specificity. <2> It depends on the prevalence of the disease. <3> It is the number of patients that give positive results among all possible individuals. <4> It is the quotient between the number of patients who give positive results for this magnitude and the total number of patients considered. <5> It is deducted directly from the minimum detectable value of this magnitude.

Answer: 4


Question: Question: Which of these foods should reduce a patient with high cholesterol from his diet? 
 Options:  <1> Cereals. <2> Vegetables. <3> Whole milk. <4> Olive oil. <5> Fish.

Answer:
3