I had C, then changed to D. I felt that the wording on D matched a little bit better since it used "reliably," but didn't account for the "can reliably," where the stimulus was talking about "CANNOT reliably predict."

so is necessary and "not sufficient" the same/interchangeable? For example if i approach a question and say that being a mammal is necessary to be a cat, that would be the same as saying being a mammal is not sufficient enough to be a cat?