The correlation between intelligence test scores and grades is generally

The correlation between intelligence test scores and grades is generally positive.

Higher intelligence tends to accompany higher academic achievement.

A negative correlation would imply smarter students score lower, which is false.

A perfect correlation is unrealistic given many other influences on grades.

No correlation is also false, since a real moderate positive link exists.

The relationship is usually moderate, not perfect, around plus 0.5 in many studies.