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 element plays a physiological role in the prevention of gastroesophageal reflux?
Options: <1> Upper esophageal sphincter <2> Angle of His. <3> Hernia of Hiato. <4> Purkinje angle. <5> Pyloric sphincter

Answer: 2

Question: Question: The folded sheet :
Options: <1> It is formed by a single polypetide chain. <2> It presents a distance between adjacent amino acids of approximately 4 angstroms. <3> It is formed by the union of two or more strands by hydrogen bonds. <4> Presents the side chains of contiguous amino acids pointing to the same side. <5> They are of two types: parallel, where the chains of the sheet go in a different direction and antiparallel, where they go in the same direction.

Answer: 3

Question: Question: What is the sampling model whose principle is to directly access the natural agglomerations of units in the population? (workers in factories, students in universities ...):
Options: <1> Stratified sampling. <2> Simple random sampling. <3> Conglomerate sampling. <4> Systematic sampling. <5> Sampling in time.

Answer:
3