Answer: a chivalric utopia
Explanation:
An appositive is a noun that follows another noun in order to provide more information about the noun.
With regards to the question, the appositive is "a chivalric utopia". Here, the appositive is used to modify the main noun which can be found in the last part of the sentence that is, Camelot. It gives more information on Camelot.
You would have to register the vehicle within 10 days of acquiring it :)
Number 3 would be the only logical choice in my opinion because everything else would be in a narrative or story of some sort. Expository essays are exclusively informational.
I believe the answer is B. Details that the narrator states directly in the text