Answer:
C. how the library was arranged
The correct answer for this would be option B. Based on the given sentence above, the highlighted part of the sentence which is "<span>who had been to the mansion before," is called an appositive phrase. This is considered as an appositive phrase because it renames or describes the noun next to it. Hope this helps.</span>
The correct option is option A.
The words in the brackets are telling the actors what to physically do, meaning it would be a stage direction.
It isn't dialogue because that is a conversation between two people.
It isn't dialect because that is how a person speaks. There is no speaking in the brackets.
It isn't narration because it isn't spoken allowed for the audience.
It isn't a description because that is too broad a term more often used for emotions.
