The correct option is C.
"Uncle Don" is the subject.
"is wearing" is the predicate.
"suit" is the direct object.
"to the party" is the prepositional phrase.
The adjective clause in the sentence is "whom everyone loves to see," which provides additional information about 'Uncle Don.' This clause begins with the relative pronoun 'whom,' linking back to the noun it describes. Thus, the correct choice is C.
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