A researcher suggests to potential study participants that if they do not participate they will suffer negative consequences. This undue influence is called .

Coercion

Explanation:

Coercion is the mechanism of persuading a person to perform an involuntary act through forcing them or making them perform under some threatening pressure.It can be used for confession, kidnapping, threatening, and other such activities.

According to the question, if participants are forced to become a part of research against their will otherwise they are threatened with negative consequences is type of coercion.

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