A 12 Year Old Boy, the Child of an Alcoholic

A 12 year old boy, the child of an alcoholic, tries beer. He continues to drink beer more and more heavily throughout his teens. Twelve years later, he is drinking nearly a case of beer every day. He has suffered many addiction-related problems during this time. Besides the probable environmental influence in his childhood, what else might account for his alcohol addiction?

A) Alcohol might decrease the actions of GABA on the dopamine neurons in his VTA, thus increasing dopamine release.
B) He might have a genetic defect that, in combination with memories stored in the limbic system, have helped support a learned addiction.
C) Alcohol might increase the actions of GABA on the dopamine neurons in his VTA, thus increasing dopamine release.
D) He might have multiple gene mutations that, in combination with memories stored in his amygdala, have helped support a learned addiction.