In follow-up experiments to his initial study, Milgram made the learner's protests more compelling by having him complain of a heart condition, then scream and plead for release, and finally refuse to answer. With this added condition,
a. the majority of participants still fully obeyed the experimenter's demands.
b. teachers were more reluctant to deliver initial shocks.
c. learners became more real and personal to the teacher.
d. fewer participants went to 450 volts.