Melita Oden Compared the 100 Most Successful Men (The a Group)

Melita Oden compared the 100 most successful men (the A group) with the 100 least successful men (the C group) from Lewis Terman's original sample of 1,500 children with genius-level intelligence. Given that the IQ scores of the A and C groups were essentially the same, what accounted for the difference in their level of accomplishment?

A) Birth order differences: A's were more likely to be only children or firstborns than C's.
B) Socioeconomic status: A's came from families that were wealthier and better educated than the C families.
C) Creativity and flexibility: C's were less creative and flexible than the A's.
D) Personality factors: A's were more goal-oriented, more likely to persevere, and had a greater desire to excel than the C's.