Greg J. Duncan and a team of researchers analyzed the effect of parental income on the academic achievement of children. Given what you've read about socioeconomic status and life chances, what do you think that Duncan found?

A. There was no correlation between class status and educational achievement.
B. Class status helped to predict High School grades, but had no relationship to later academic success.
C. Children from working class families are more likely to attend and graduate from college, as they have better work ethics.
D. Parental income is strongly correlated with academic achievement, especially in low-income families.
E. Parental income only seems to matter for upper-middle-class families; other social classes have more or less the same rates of college and high school graduation.