Involves purposely misleading participants in a study and must be described when participants are debriefed.

The correct answer is A. Deception.

Deception in research refers to intentionally misleading participants about certain aspects of the study in order to prevent bias or alter behavior. It is important that participants are debriefed afterward to explain the nature of the deception and the reasons for it, ensuring they understand the study’s true purpose and that their rights and well-being are protected.