Which of These Would Provide the Strongest Evidence to Support

Which of these would provide the strongest evidence to support the theory that schizophrenia is due to socioeconomic factors?

A) evidence showing that people of lower socioeconomic status have higher rates of schizophrenia than those of higher socioeconomic status
B) evidence showing that the risk of schizophrenia is positively correlated with the number of life stressors one has experienced
C) evidence showing that the rate of schizophrenia changes after people have moved from a higher to a lower,or from a lower to a higher socioeconomic status
D) evidence showing that the risk of schizophrenia is negatively correlated with one's annual income