Answer: C) The appositive phrase contains nonessential material.
Step-by-step explanation: An appositive is a noun or noun phrase that renames or gives further information about another noun right beside it. In the given sentence, we can see an example of an appositive in the phrase "a notable quality of her work" this appositive renames the noun phrase "her character development" and it contains noessential material (the sentence would still make sense without the appositive).