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'.

Ex Input:
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.

Ex Output:
2


Ex Input:
Question: A drug with a seemingly monocompartmental distribution pattern is administered in the form of i.v. perfusion. at a constant speed of 20 mg / h for 48 h. Once the perfusion is finished, three blood samples are taken, which, when analyzed, allow the calculation of the primary parameters of the model Kel = 0.0495 h-1, concentration at the end of the perfusion (C48h) = 5,553 μg / mL, Vd = 66 L. At what time would the steady state be reached ?: 
 Options:  <1> 14 h. <2> 28 h. <3> 42 h. <4> 56 h. <5> 70 h.

Ex Output:
5


Ex Input:
Question: The analysis by potentiometric redisolution is characterized: 
 Options:  <1> By using the square wave as an element of excitation. <2> Because the redisolution stage is carried out without agitation. <3> Because the reoxidation step is carried out by an oxidizing agent. <4> Because currents are measured in the redisolution stage. <5> Because the redisolution is carried out at constant potential.

Ex Output:

3