DSAT R&W: Khan Academy Paired Passages (Advanced), Pt. 4: Cognitive Dissonance 

Yes. The main issue with B is that it doesn't reflect Bem's criticism of Festinger's idea. As it says in the first sentence of Passage 2, Bem's theory "challenges the assumption that people always have a clear and stable belief system that guides their actions." In other words, he is challenging the assumption underlying Festinger's theory (namely, that "people experience psychological discomfort...when they behave in ways that are inconsistent with their beliefs"). Answer choice B suggests that Bem basically does agree with Festinger's theory and its underlying assumptions. That is, for Bem to "recommend that Festinger test his theory by experimenting with the degree of inconsistency between people's beliefs and their behavior" would imply that he (Bem) accepts the idea that people have clearly established beliefs in place before acting -- beliefs that their actions could either be consistent or inconsistent with (to varying degrees). But again, the point of passage 2 is that Bem does not accept this idea, since he "argues that people sometimes infer their beliefs from their own behavior." Does this make sense?