Question: In a meta-analysis of 15 studies, the incidence of myocardial infarction with the new drug Tromboclean is 10.8% compared to 8% with heparin. The relative risk is 1.35, with a 95% confidence interval of 1.15 to 1.50 and absence of significant heterogeneity between studies (p-value of heterogeneity = 0.95). Point out the CORRECT answer: 
 Options:  <1> The heterogeneity is not significant, which suggests that the results are inconclusive. <2> Trombo Clean presents a risk of myocardial infarction similar to that of heparin. <3> It can not be ruled out with a 95% confidence that Tromboclean reduces the risk of myocardial infarction by 50%. <4> Thromboclean increases the absolute risk of myocardial infarction between 15% and 50%. <5> Heparin presents a significantly lower risk of myocardial infarction than Tromboclean.
5