Mary is trying to determine how to conduct an ethical research study on stress levels in children. she has decided to consult the ethical principles of psychologists and code of developed by the american psychological association (apa).

The correct answer is conduct.

The ethical code of conduct developed by the American Psychological Association (APA) refers to a guide of ethical standards and principles psychologists must adhere to, when conducting psychological experiments and research studies on human or animal subjects. Psychologists must adhere to APA's Code of Conduct to minimize any harm or distress a psychological study might pose for its participants.  

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