It could be argued that participants in Muzafer Sherif’s (1936) study converged in their estimates of the amount of movement of a point of light because they were avoiding public embarrassment or social censure from other participants. Sherif demonstrated that this was unlikely when he found similar results:
a. when participants completed the task with their friends.
b. two years later.
c. when participants later completed the task alone.
d. when participants completed an auditory task in groups.

C). When participants later completed the task alone.

Explanation:

Muzafer's proposed his study of social conformity for which he selects the autokinetic effect and reveals that 'informational social influence'(as a stimulus) can help the participants estimate the portion of the movement of dot light as 'they were avoiding public embarrassment.'

As per the question, Sherif can counter this study when he discovered similar results 'when participants later completed the task alone' without any kind of informational social influence or ambiguous stimulus. This contradicts Sherif's study and hence, option C is the correct answer.

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