Research into the Effects of All Known Compounds in Marijuana

Multiple Choice

Research into the effects of all known compounds in marijuana on the user's brain

A) has consistently failed to show any adverse effect.
B) generally shows only short term damage to the hippocampus region of the brain, which resolves with abstinence.
C) reveals long term cognitive impairment for short term or social users.
D) is relatively rare and very limited in scope.