TASK DEFINITION: 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'.
PROBLEM: 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.

SOLUTION: 2

PROBLEM: Question: The set of means and systems that facilitate the contact of the infectious agent with the recipient subject corresponds to: 
 Options:  <1> Source of infection. <2> Habitat. <3> Transmission mechanism. <4> Biotope <5> Reservoir.

SOLUTION: 3

PROBLEM: Question: For a skeletal traction to be effective, the principles that must be met are: 
 Options:  <1> Contraction, continuity and body alignment. <2> Body alignment and joint mobility. <3> Joint mobility and continuity. <4> Contraction and body alignment. <5> Continuity, body alignment and joint mobility.

SOLUTION:
1