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'.

Question: The main indication for using 4 drugs in the initial treatment of tuberculosis is: 
 Options:  <1> Affectation of the central nervous system. <2> High prevalence of primary resistance to isoniazid. <3> Cavitated and extensive pulmonary tuberculosis with large bacillary load. <4> Disseminated tuberculosis associated with HIV infection. <5> Extrapulmonary tuberculosis in immunodepressed patients of any origin.
2

Question: When comparing the characteristics of pragmatic or confirmatory clinical studies with explanatory or exploratory clinical studies, which of the following is an advantage of the former? 
 Options:  <1> Information about subgroups of patients representative of the usual clinical practice. <2> Very homogeneous sample, with little variability. <3> Greater capacity to detect differences in the effectiveness of interventions. <4> Greater internal validity <5> Smaller sample size
1

Question: The formation of the complex called Aminophylline improves the solubility of one of the following drugs: 
 Options:  <1> Theophylline <2> Digoxin <3> Ampicillin <4> Thioridazine. <5> Ciclosporin

1