He was wearing an expensive watch
I would say B expensive because it has a AN and none of the other words fit correctly into the sentence.
The sentence 'He was wearing an _______ watch' can be completed with several options. Among them, 'expensive' is a strong choice as it emphasizes the quality and status of the watch. Other options like 'gold,' 'valuable,' and 'designer' would also fit, depending on what one wants to highlight.
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