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: The water used in the preparation of medicated syrups must:
Options: <1> Be sterile <2> Be purified or distilled water. <3> It is highly recommended that it contain dissolved carbon dioxide. <4> Contain dissolved calcium ions. <5> Contain an adequate proportion of magnesium ions.

Answer: 2

Question: Question: According to the phenomenon of social facilitation when a person develops a task poorly learned in the presence of others, the execution of said task:
Options: <1> It improves slightly. <2> It improves substantively. <3> It does not change. <4> Gets worse. <5> It is not predictable.

Answer: 4

Question: Question: The type of epidemiological study indicated to evaluate, in a population initially exempt from the health problem under study, the association between a risk factor and the onset of the disease is:
Options: <1> Randomized clinical trial. <2> Quasi experimental. <3> Ecological studies <4> Cases and controls study. <5> Cohort study.

Answer:
3