A Study Has Found a Positive Correlation Between Smoking Cigarettes

question 137

Multiple Choice

A study has found a positive correlation between smoking cigarettes and schizophrenia. Which is/are possible explanations for this finding?

• A) A third variable could be causing both.
• B) Some property of nicotine could be part of the cause of schizophrenia.
• C) Something about the nature of schizophrenia could be a factor in the cause of smoking.
• D) All of the above are possible explanations for this finding.