Final answer:
Vietnam, China, and Taiwan have a legitimate Exclusive Economic Zone claim to the South China Sea.
Step-by-step explanation:
The countries that have a legitimate Exclusive Economic Zone claim to the South China Sea because they are recognized as sovereign states by the United Nations and have a coastline that borders the South China Sea are Vietnam, China, and Taiwan.
Australia is not recognized as having a coastline that borders the South China Sea, therefore it does not have a legitimate Exclusive Economic Zone claim to the area.
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