Final answer:
The word 'stubbornly' in the sentence is an adverb that describes how Kristen is independent.
Step-by-step explanation:
The word 'stubbornly' in the sentence is an adverb. It modifies the adjective 'independent' by describing how Kristen is independent. An adverb is a word that typically modifies a verb, adjective, or other adverb. In this case, 'stubbornly' describes the manner in which Kristen is independent.
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