One research study found that a recovered heroin abuser experienced nausea and withdrawal symptoms when he returned to the neighborhood where he had previously used heroin and experienced withdrawal effects. this research supports the idea that may be a significant factor in the development and maintenance of substance addiction.

Classical conditioning.

Explanation:

Classical conditioning is a form of association between a conditioned stimulus with an unrelated one which produces a behavioral response. In this case, the recovered heroin abuser experienced withdrawal symptoms when he returned to the place where he had previously used the drug and experienced the same effects.

did you study? i cant if you didnt study

answer; i believe the correct answer is (a) the correlation between the cause variable and outcome variable is zero;