Many people visit San Diego every year because of the mild year round climate, the beaches, and Sea World. But its most famous attraction ..........  

Many people visit San Diego every year because of the mild year round climate, the beaches, and Sea World. But its most famous attraction is probably the exceptionally fine San Diego Zoo.

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Mana kata referensi dari kata yang dicetak tebal?

kata "its" mengacu pada "San Diego".