In Their Study of Happiness and Success in College, Sheldon

In their study of happiness and success in college, Sheldon and Houser-Marko evaluated freshmen students' reasons for attending college according to the extent to which their reasons reflected external, introjected, identified, or intrinsic motivations. What reason/motive type was most related to higher grades, personal goal fulfillment, better social and emotional adjustment, and personal development?

A) external - consistent with reinforcement theory
B) introjected and external consistent with control theory
C) intrinsic - consistent with flow theory - turning work into play
D) identified and intrinsic - consistent with self-concordance theory