D. Impossible to Disprove
The word “conclusive” means indisputable (Note: literal meaning = denotation). In the sentence, we can see that the statement says that “because of evidence….” Evidence is something that can provide a basis for thinking something happened—proof—in so much that one need not have had to experience something first hand or directly in order believe it happened. Thus, because the attorney made a claim that evidence provided enough information in order to make something indisputably believable without question, we know that what is denoted is "impossible to disprove."