<span>C. She lives on the twentieth floor of an old apartment building somewhere in Manhattan.
This option is accurate since it contains articles and modifiers that are grammatically correct:
i) "the" is used before the word "twentieth" (a noun modified by ordering- i.e. first, second, third, and so on...)
ii) "an" is used before the word "old" (which begins with a vowel)
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Well it is not stop listening, or make an effort too attend, I am sure that assign meaning is correct.
This words simply means not easily convinced. Or even having doubts.
The narrator is nervous about choosing between Dauntless and Abnegation.
