The passage's conclusion is that "as long as there are distinct cultures, there are no values shared across cultures." Therefore different cultures and shared values cannot coexist.
Answer choice (B) describes a future in which we "all share the same culture and the same values." This means that there are no longer different cultures, so (B) does not contradict the statement made in the passage.
Does that make sense? Please let us know if you have any other questions.