The author uses the term "realistic" throughout the passage to refer to which one of the following qualities of a film?

I am unsure how to select B as the correct answer, because it appears that multiple definitions of "realistic" are offered throughout the passage. For example, line 9 of the passage does seem to support B. However, lines 39-40 seem to suggest that Bordwell believes musicals to be "realistic" because they allow viewers to identify its genre as a musical and thus understand the story. This seems to lend support for A and perhaps even D (although the language "easily" does seem a bit strong). Finally, line 50--"even the viewer aware of the film's genre cannot remain entirely unfazed by the break in the film's 'reality'". seems to refer to the film's narrative plotline. This appears to offer support for A. Will someone clarify how to eliminate these other answer choices and how to identify answer choice B as correct? Does this relate to the author's use of quotations ("realism" and "realistic") in the latter half of the passage, perhaps suggesting that they do not actually support those definitions? Thank you!