What Would Be Exemplified by Poor "Overall Flow of Logic

What would be exemplified by poor "overall flow of logic in the study," in terms of the second step of critical appraisal?

A) The title of the study mentions "the effect of" but the study design is simple descriptive.
B) There was a 60% dropout; nonetheless, the researchers claimed that the sample was representative.
C) Statistical analyses used are all coherent with the variables' levels of measurement.
D) The study framework is gratuitous. It does not, in the slightest, help to explain the relationship between the principal study variables.
E) The problem statement and the purpose of the study aren't closely related. It seems like a big leap to get from the problem to the gap, and to the purpose.