We learn from the stimulus that art historians have concluded that pre-restoration interpretations of the frescoes may no longer be appropriate post-restoration.
Why? The colours that the art historians studied (i.e. pre-restoration) may differ from the works' original colours.
There is a bit of a gap in the reasoning presented to us. We know that the colours studied by the art historians may have differed from the works' original colours. But what does this have to do with interpretation?
Answer choice (C) is correct because it tells us that the colours of an artwork are relevant to the work's appropriate interpretation.
Answer choice (B) is incorrect because it adds new information (i.e. the artist's intention) without explaining the relationship between colour and interpretation.
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