Why Does the Predictive Validity of General Aptitude Tests Decrease

Why does the predictive validity of general aptitude tests decrease as the educational experience of the students who take them increases?

A) More educated students have taken aptitude tests so frequently that for them such tests are no longer pure measures of aptitude.
B) Comparisons of mental age with chronological age are inadequate for
C) assessing the aptitude of older and more educated students.
D) There is a relatively narrow range of aptitude test scores among students at
E) Among more educated students, motivation has a much greater effect on academic success than does aptitude.