In an Alternative Version of His Original Experiment,Stanley Milgram Used

In an alternative version of his original experiment,Stanley Milgram used two experimenters,who began to disagree with each other when the participants administered 150 volts and the learner began to complain.In this variation,participants refused to continue.According to the authors of your text,this variation demonstrates the importance of ____ in influencing obedience.

A) clear informational influence
B) unanimous normative influence
C) the foot-in-the-door effect
D) the door-in-the-face effect