The passage says some people argue that Vierne's organ symphonies are not religious music. This is contrasted with Handel's work, which sets familiar religious texts to music and is considered religious music. However, the critic disagrees with this argument, implying that s/he believes Vierne's symphonies are religious music. S/he says that hearing Vierne's symphonies in Notre Dame cathedral demonstrates that they are divinely inspired.
Though subtle, the critic is shifting the meaning of the word "religious." In the beginning of the passage, the critic references religious music as being based on religious texts. At the end, the critic references religious music as being "divinely inspired." Are these the same? No, the first definition has to do with the substance the music was derived from whereas the second definition has more to do with the feeling of the music in a specific setting. This shift suggests that the critic confused different meanings of the word "religious," which makes (B) the correct answer.
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