which statement about addiction and genetics is true?
a. if both parents are alcoholics/drug addicts, their offspring will also be alcoholics/drug addicts, but if only one parent is affected, any offspring has a 50% chance of developing a problem
b. the addiction gene has been identified
c. a large number of genes influence susceptibility to addiction
d. if drug or alcohol problem do not run in a family, other family members will not develop a problem either