The correct answer is A, 'bright'. A predicate adjective is an adjective describing the subject of a sentence with a linking verb.
The color of her dress was quite bright.
In this sentence, the word 'bright' describes the subject, 'color', because the dress was a bright color. B is incorrect because 'quite' is an adverb describing 'bright'. C is incorrect because 'dress' is the object of the preposition 'of'. D is incorrect because 'her' is a possessive pronoun describing 'dress'.
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