Students Who Completed a Study Skills Course Raised Their Grade

Multiple Choice

Students who completed a study skills course raised their grade point averages.Can we conclude that the course caused their improvement?

A) Yes, because the scientific data was collected.
B) Yes, because a negative correlation exists between these students' grade point averages before and after taking the course.
C) Yes, because the course resulted in a self-fulfilling prophecy.
D) No, because there was no control group.