Answer:
The word that is a predicate adjective in this sentence is D) tired.
Explanation:
A predicate adjective is an adjective that follows a linking verb (the verb that connects the subject with the descriptive adjective) and modifies the subject. It is important to avoid confusion between the predicative adjectives and the attributive adjectives, that are usually placed inmediately before the noun they modify (in this case, fat and brown that are modifying cat.)