To the question put up in the last post :- 'C', and you've got to believe me for it's the most precise and best answer among the choices. Yes, there's a logic and rationale behind it, which is too subtle for all our ingenious and ingenuous minds, so as to promptly strike of C as the most plausible wrong answer to that question. However, the explanation goes something like this:
Choi's statement is a comparison among individuals: If my parents have earned doctorate and your's didn't, then Chod says that the odds are better that I will earn a doctorate than you will. Choi's claim goes no further. He doesn't claim that children of doctors are guranteed to earn doctorates, and he doesn't even claim that they are likely to earn doctorates. He merely claims that these children are more likely to earn doctorates than their counterparts who do not have a parent that earned a doctorate. So even if only 5 percent of doctor's children earn doctorates themselves, Choi's claim is still correct as long as fewer than 5 percent of children whose parents didn't earn a doctorate went to earn a doctorate themselves.
Thus the irrelevancy of Hart's 70 percent figure, which gives us information on a different goup -- those who already earned their doctoral degree.
Because she has shifted the scope, the data Hart presents can be true and still have no bearing on Choi's claim. An example :Suppose that there are 10 people in the world with doctorates. Choi merely claims that children of these people are more likely to get doctorates than children of other people. Hart comes along and says that of the 10 people, say , 8 of then(70%) come from doctorate-less parents. Does that alter Choi's claim in any way? No. All other factors being equal, the children of those doctors could still be more likely to earn doctorates, even if most doctorate holders don't have that particular heritage. Because of this, Hart's considration doesn't contradict Choi's claim in any way, and we can therefore say that Hart's statement is consistent with it.