In Asch's Study of Conformity, Which Involved a Comparison of the Lengths

In Asch's study of conformity, which involved a comparison of the lengths of different lines, subjects were told that the experiment was about perceptual judgment. Telling subjects this:

A) involved the unnecessary use of deception, which Asch later regretted
B) aroused a great deal of suspicion because the line-judging task was too easy
C) was part of the experimenter's cover story
D) created a high level of mundane realism in the experiment