Some have suggested that the results of Milgram's obedience study may have been due to the __________ effect.

A) reciprocity
B) indebtedness
C) foot-in-the-door
D) returning-a-favor

The foot-in-the-door effect refers to the tendency for people to comply with a smaller request in order to increase the likelihood of agreeing to a larger request later on. In Milgram's study, the participants were initially asked to administer a small shock, and then gradually asked to administer higher and higher shocks. This gradual increase in the severity of the requests may have played a role in the participants' obedience, as they may have felt obligated to continue complying with increasingly severe requests due to the foot-in-the-door effect.