Forty to 60 percent of students report, in anonymous surveys, that they plagiarized at least once as undergraduates, and evidence indicates that plagiarism also occurs in our medical and business schools. Researchers have found that students who plagiarize are more likely to engage in subsequent professional misconduct such as falsified research results and fraudulent business practices. Thus, a reduction of academic plagiarism will lead to a reduction of professional misconduct. Which one of the following most accurately describes a flaw in the reasoning in the argument? ['The argument presumes, without providing justification, that a certain phenomenon is the only factor contributing to the incidence of a certain other phenomenon.', 'The argument infers the existence of a causal connection merely on the basis of an association.', 'The argument takes for granted that a certain behavior is more prevalent among members of one population than it is among members of another.', 'The argument introduces one subject for debate, but proceeds to give premises relevant to a different subject.']