To ensure that participants genuinely believed the experimental setup was real and that the 'learner' was receiving actual electric shocks, which of the following procedures did Milgram (1963) implement before the learning task commenced?
Having the 'learner' loudly protest and demand to be released during the initial practice trial at 15 volts
Showing the 'teacher' a signed safety certification from the university's physics department to verify the equipment's legitimacy
Administering a genuine sample shock of 45 volts to the 'teacher' using the shock generator
Allowing the 'teacher' to inspect the internal wiring and battery pack of the shock generator to prove it was fully functional
