What Does Research Data Show Is the Relationship Between Gene(s)

What does research data show is the relationship between gene(s) and substance abuse?

A) No one gene causes substance abuse or dependence.
B) One dominant gene is found in 90% of people with substance abuse disorders.
C) One recessive gene is found in 90% of people with alcohol or nicotine dependency.
D) No genes have been found to be linked to substance abuse.