Question: If you want to study the efficacy and safety of a new cytostatic for a specific oncological process and, at the same time, contrast the efficacy that adds a new monoclonal antibody to this treatment, what would be the most appropriate study design? 
 Options:  <1> Parallel test. <2> Cross test <3> Factorial test. <4> Sequential test. <5> Test of n = 1.
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