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: Which of the following enzyme complexes catalyzes the reduction of molecular oxygen to water during oxidative phosphorylation? 
 Options:  <1> ATP synthase. <2> Cytochrome c oxidase. <3> NADH-Q oxide-reductase. <4> Q-cytochrome c-oxide-reductase. <5> Succinate-Q reductase.

Answer: 2


Question: Question: It allows to compare proportions of two independent samples the statistical test: 
 Options:  <1> From McNemar. <2> Of Snedecor. <3> Of the median. <4> Exact Fisher. <5> U of Mann-Whitney.

Answer: 4


Question: Question: The characteristic Rovsing sign in acute appendicitis consists of: 
 Options:  <1> Pain in the epigastric pressure when applying a firm and persistent pressure on McBurney's point. <2> Acute pain that appears when the appendix is ​​compressed between the abdominal wall and the iliac crest. <3> Passive rebound sensitivity in the abdominal wall. <4> Loss of abdominal sensation when contracting the muscles of the abdominal wall. <5> Pain at McBurney's point when compressing the lower left quadrant of the abdomen.

Answer:
5