Aresearcher is interested in determining how frequently bullying behavior occurs in real-life settings. this researcher would best be advised to use the

a) case study design.
b) correlational design.
c) experimental design
d) naturalistic observation design.

naturalistic observation design

Explanation:

The naturalistic observation design contain research steps that involves observing the spontaneous behavior of subjects in their natural environment. This method can be used by researchers or psychologists in cases where the study cannot be performed under laboratory conditions or when the costs of such study is very high.  

The researcher can record the frequent bullying patterns he or she sees in such real-life conditions.  

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