Final answer:
The independent variable in Sherif's study was the number of people making the estimation, and the dependent variable was the estimation of how far the light moved.
Step-by-step explanation:
In Sherif's 1935 experiment, the independent variable was the number of people making the estimation, and the dependent variable was the estimation of how far the light moved. The correct answer to the student's question is c) The number of people making the estimation; estimation of how far the light moved. This design allowed Sherif to observe how individuals' judgments of the autokinetic effect were influenced by the presence of others, reflecting informational social influence in ambiguous situations.