The correct answer is D. A prepositional phrase means that it starts with a preposition. And in these examples, D is the only one that starts with a preposition "on".
A framed narrative happens when the author uses a story and its characters to tell you another story (a story within a story... a storynception). Here, we can observe a character doing a grand opening, and he starts to introduce a character when he says "<span><em>I want to tell you of a marquis, whose actions, even though things turned out well for him in the end, were remarkable not so much for their munificence as for their senseless brutality."
</em>Therefore, you best answer is option B.<em>
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True. this is going to show what the paragraph will be about