Final answer:
The linking verb in the sentence is 'became' and the predicate noun is 'winner'.
Step-by-step explanation:
The linking verb in the sentence is 'became' and the predicate noun is 'winner'. The subject of the sentence is 'Boris Becker'. In this sentence, 'became' links the subject 'Boris Becker' to the predicate noun 'winner', which describes his achievement in becoming the youngest winner of the men's Wimbledon singles tennis tournament.
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