Choi: All other factors being equal, children whose parents earned doc

please say the correct answer with explanation

No choice here is correct, though I bet the OA will be given as D.

The extra datum that could reconcile these two observations would be the ratio—among whatever ENTIRE population is relevant here (most likely a single country, or other unit for which identical census data is available throughout)—of people with children who have doctorate degrees to people with children who do NOT have such degrees.

We would presumably find that only a minuscule proportion of people—most likely a single-digit percentage—have PhD degrees.
As long as that is true, then, even if ALL of the doctorate holders' kids go on to earn doctorates themselves (a massive exaggeration of what Choi is saying), Hart's assertion could still very easily be true.

The OA will probably be given as D, just because that's the only choice that isn't instantly wrong right on its face. (You don't have to read past Hart's first word to see that E is false. Neither A nor B has any possible relevance. And C doesn't even mean anything, because neither speaker is actively making any sort of "case"—in other words, an argument with a conclusion—in the first place.)
...But D isn't right, either, because the entire exchange can function without ANY absolute numbers. Both speakers' assertions are in terms of percents/fractions/other RELATIVE figures (Hart's explicitly, Choi's because "more likely" must be interpreted in terms of probabilities), and neither assertion requires any absolute numbers to make sense. As explained above, the only necessary datum that's missing here is the ratio, or relative proportions, of parents who have PhD's and parents who do not.

how can B be the answer as it is making choi assertion wrong?

Explanation from KapTeacherEli

Step 1 of the Kaplan Method for Critical Reasoning: Identify the Question Type

The first thing we need to do is figure out what is going on with the question, and the word 'explain' in the the stem gives it away: this is an explain question. As soon as we see this, we know we will be looking to explain a seeming contradiction between two facts.

Step 2:Untangle the stimulus

We know what to look for in the question type: a paradox. So our task is to identify the contradiction! Here, Choi states that all else being equal, PHD children get more PHDs themselves. Hart, however, states that the majority of PhD students get PhDs with no doctorates in their families. So the paradox is:

"Having parents with PhDs is a factor in getting a PhD oneself, yet most PhDs do not have doctor parents."

Step 3: Predict the Answer

We need to resolve the paradox. Fortunately, we have a great starting point in Choi's first line: "All other factors being equal." Aha! Choi is talking about theory; Hart, however, is talking about real numbers, where all other factors aren't equal! So, we can predict an answer that explains both Hart and Choi's position:

"There are factors that have a larger impact on who gets a doctorate than having parents with a doctorate"

If this is true, then Choi is right because all else being equal, parent will be a factor, but Hart is right because things like money, education, and career path have a much larger impact, explaining his 70/30 number.

Step 4: Evaluate the Answer Choices

Choice (B) matches our prediction, and is the correct answer.

I'm not sure if I completely agree with the OA. I went for D but even that needs a lot of assumptions.

If I consider two groups - Group A (Children of Doctorate parents) and Group B (Children of non-Doctorate parents)
** Not considering single parent being Doctorate as it is not discussed

Let's say Group A is 100 and Group B is 1000 (these figures are the key to the reconciliation of their statements)

As per Choi, members of Group A are more likely to get a Doctorate than Group B. Say for e.g. 30 members go on to achieve a doctorate. While from the other group we have only 70 and this number corresponds to the lower likelihood of achieving a Doctorate than Group A.

In the Overall pool of Doctorates (30 + 70), group B still gets 70%.

The only time this will not work is when the overall pool of members of Group A and Group B are comparable or Group A has more members than Group B

If I manipulate the members of Group A and/or Group B, we can have varying outcomes. So along with assumptions, I'll have to side with D because none of the others fall in line with the question stem.

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