A researcher decides to tell participants something false about a research session in order to mislead them. The researcher is using:

Active deception means deliberately giving participants false information about the study to mislead them.

Naturalistic observation records behaviour in its normal setting without any intervention.

Role playing asks participants to act out an assigned situation rather than deceiving them.

Dehoaxing informs participants afterward about any deception that was used.

Passive deception withholds information rather than stating outright falsehoods.

Ethics boards permit deception only when no alternative exists and debriefing follows.