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 suggests that people are more likely to comply with a large request if they have already complied with a smaller, related request. In Milgram's study, participants were initially asked to administer a relatively low-level shock, and then gradually increased the level of shock as the study continued. This could be seen as an example of the foot-in-the-door effect, as participants were more likely to comply with the larger request (administering the highest levels of shock) after having already complied with the smaller request (administering the lower levels of shock).