The Relationship Between Chronic Marijuana Use and Educational Achievement

The relationship between chronic marijuana use and educational achievement

A) is most likely explained by the fact that marijuana causes cognitive deficits.
B) is a correlational relationship that does not merit further study.
C) may be explained by the social environment of marijuana users and their values concerning education.
D) has only been measured in terms of absenteeism, which probably reflects motivational variables more than academic factors.