According to the Research, the Relationship Between Academic Achievement and Self-Determination

According to the research, the relationship between academic achievement and self-determination (i.e., the amount choice and personal control over one's environment) is both positive and strong.However, researchers doing work in your classroom found a correlation of -.15 between the number of student choices and grades.You should conclude that:

A) the classroom research is incorrect.
B) there is a low negative correlation in the classroom research.
C) removing student choices will help improve students' grades.
D) increasing student choices will help improve students' grades.