6. (C)
Question type: Identify A Flaw
The fact that rounded arches and symmetry are a primary reason for why Classical Roman architecture is beautiful doesn’t mean that rounded arches and symmetry are sufficient for something to be beautiful. The same reasoning can be applied to the drama of post-modern architecture. Therefore, one cannot ensure beauty and drama by just including those few characteristics. Furthermore, beauty and drama often rely on the careful juxtaposition of features _ it could be true that the melding of beautiful and dramatic features creates something that is neither beautiful nor dramatic.
Answer choice (C) addresses these primary flaws, and is therefore correct.
(A) is outside the scope of the argument.
(B) is outside the scope of the argument.
(D) would only be relevant to an incorrect understanding of the author’s point.
(E) is outside the scope of the argument.