An Investigator Found No Significant Correlation Between the Grades That

An investigator found no significant correlation between the grades that teachers earned in education courses and the principals' ratings of those teachers.The investigator should conclude

A) principals are unable to recognize good teaching.
B) education courses have no influence on teacher performance.
C) grades in education courses are unrelated to teacher success.
D) grades in education courses are related to teacher success, but the present measuring instruments are inadequate for showing this relationship.
E) None of these is true.