Its either C, or D... but I'm leaning towards C.
I hope I helped and good luck.
Appositive is a noun that defines/clarifies another noun in a sentence.
Example;
Mrs. Sue, <u><em>our piano teacher</em></u>, is having a baby next week.
Yes it makes sense but the wording is a little strange maybe rearrange it a little.
The antonym for the word is bored