Last Year, Jacqueline Had a Psychology Course and a Physics

Multiple Choice

Last year, Jacqueline had a psychology course and a physics course. She had more quizzes in the psychology courses and was earning better grades compared to the physics course. She devoted more than half of her study time to psychology last year. This year, she has another psychology course and another physics course.  This time she has more quizzes in physics, and her grade is also better in physics. She still spends more than half of her time studying for psychology. According to the matching law, this distribution of effort can be accounted for by _____.

A) self-control
B) COD
C) bias
D) optimization