单选题public class Person { private name； public Person（String name） { this.name = name； } public boolean equals（Object o） { if（ !o instanceof Person ） return false； Person p = （Person） o； return p.name.equals（this.name）； } } Which is true？（）A Compilation fails because the hashCode method is not overridden.B A HashSet could contain multiple Person objects with the same name.C All Person objects will have the same hash code because the hashCode method is not overridden.D If a HashSet contains more than one Person object with name=”Fred”， then removing another person， also with name=”Fred”， will remove them all.
单选题
public class Person { private name； public Person（String name） { this.name = name； } public boolean equals（Object o） { if（ !o instanceof Person ） return false； Person p = （Person） o； return p.name.equals（this.name）； } } Which is true？（）
A
Compilation fails because the hashCode method is not overridden.
B
A HashSet could contain multiple Person objects with the same name.
C
All Person objects will have the same hash code because the hashCode method is not overridden.
D
If a HashSet contains more than one Person object with name=”Fred”， then removing another person， also with name=”Fred”， will remove them all.
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