Though i am still in the process of 'digesting' the logic behind the correct answer, the OE has definitely made me realise a few points that i have been overlooking all this while.
1) Correlation DOES NOT imply Causality
2) Correlation is a generic trend, it doesnt warranty specific outcomes (avoid this for inferences mostly).
Here's a link for more on this-
https://magoosh.com/gmat/2013/gmat-criti ... pulations/Below is the OE from Magoosh.(B) is the credited answer. In the population view, higher education level is correlated, on average, with higher income, but this doesn't apply at the individual level. Indeed, despite the overall population pattern, it would certainly be possible to find someone with a sixth-grade education who struck a fortune and therefore was richer than many people with Ph.D.'s. It wouldn't be likely, if we picked a random person with a sixth-grade education and a random Ph.D., but it would be possible.
(A) plays on the correlation-causality fallacy. Chess is correlated with education level, but doesn't "cause" education level. Education level is correlated with income, but doesn't singlehandedly "cause" income. There is no reason to conclude what (A) says.
(C) plays on the fallacy of scope. Yes, there's a correlation in the overall population, but just because Jane has a Ph.D. and Chris doesn't even have an B.A., we can't automatically assume that Jane is better at chess.
(D) is tricky. The "education level" variable implied the idea of "length of time being educated", but that's not explicitly part of the variable. The question very clearly says one of the last three categories is "Master's Degree", so all master's degree would fall into this category, irrespective of the duration of the program.
(E) also plays on the correlation-causality fallacy. In general, folks who are more proficient at chess are more likely to pursue higher degrees, but it's not that step-by-step in their year-by-year learning process, they are steadily learning more about chess. In other words, the education does not strictly "cause" the proficiency in chess.